KEEN MCHUGH DIDN'T choose to go to E*Trade — the choice was made for him in a corporate boardroom. He had spent several happy years with Harrisdirect, another discount brokerage, but in the latest round of the consolidation sweeping the discount broker industry, McHugh and thousands of other Harrisdirect customers instantly became customers of E*Trade one day in January.

With control of four accounts that hold assets in the seven-figure range, McHugh, of Charlotte, N.C., qualified for cheap $8 commissions at both brokerages. But he says the level of service he was used to at Harrisdirect suddenly disappeared. When he asked for the automatic dividend reinvestment to be halted in one of his accounts, he says, it took four e-mails and two telephone calls to complete his request. When he sought rebates promised him for trades in late January and early February, he had to look up his trade history and read it over the phone. "You send them an e-mail, and it's quicker watching girders rust than getting a reply from those people," McHugh says. "I'm not going to put up with this kind of nonsense." McHugh, a registered broker himself, plans to transfer his accounts to another firm.

McHugh isn't the only investor running into problems as the discount broker industry goes through one of the biggest waves of mergers in the industry's short history. In the fourth quarter of 2005 alone, mergers affected 3 million accounts and nearly half a trillion dollars in assets. The latest round of merger mania redrew the broker landscape: Ameritrade combined with TD Waterhouse to form TD Ameritrade, while E*Trade acquired Harrisdirect and then BrownCo. Transferring hundreds of thousands of accounts from one brokerage to another can be daunting, and the brokers going through mergers have taken heat from customers worried about glitches, poor service, and a new set of trading tools and commission levels.

Indeed, an annual survey from J.D. Power found that even though overall online-broker satisfaction was up slightly last year, each of the brokers involved in a merger had a lower score on the overall satisfaction index. Internet chat boards are packed with messages from angry customers grousing about being forced to switch firms.

Brokers argue that not everyone is losing out during the consolidation: For starters, the nearly $2 trillion in accounts at Fidelity and Schwab comprises 80% of the cash in discount brokers, and neither company was involved in a merger. Even at E*Trade, President Jarrett Lilien says the Harris takeover was the rare "perfect storm"; the merger was complicated by everything from software bugs to a surging market to differences in the cultures of the two brokerages. "Harrisdirect had much higher service levels," he says, "while E*Trade was more for the people who didn't need much help." Nor is the news for investors who do find themselves at a new firm all bad. Commissions at TD Ameritrade are now $9.99, much cheaper than the $17.95 for small investors at the old TD Waterhouse. Brown customers will soon be able to trade bonds online at E*Trade, which wasn't possible at their old broker. Then there's Warren Potas of Washington, D.C., who's used Waterhouse for years, enduring a Web site that works so poorly on his Macintosh he has to go to another site to get stock quotes. Potas says he is looking forward to trading from Ameritrade's platform and gaining access to a new set of tools.

Still, the picture may get worse before it gets better. Some industry experts say the current round of consolidation is just heating up. Joe Moglia, CEO of TD Ameritrade, told SmartMoney he expects to see only three large discount brokerages left when the mergers are finished.

What do all these changes mean for the consumer? The bottom line is that you may have to shop around — better that you choose a broker rather than allowing a merger to make the choice for you. That's where our survey comes in. We opened accounts at 14 brokers, where we bought and sold big stocks, little stocks, corporate bonds and covered calls. We pestered customer-service centers by phone and e-mail to see whether or not they could answer our questions, and how quickly. To get a real-world sense of how much you'll pay to trade a mutual fund, we found out who charges a hefty transaction fee for out-of-network funds. (Hint: Beware Fidelity and Schwab.) We pored over 1099 tax forms to see which had the information you need on Apr. 15; we checked account statements for readability; and we ran Web sites through their paces, grading them on ease of use and efficiency.

We also added a new variable this year: rates on cash. After the dramatic rise in short-term interest rates, payouts range from a stingy 0.95% (TD Ameritrade) to a stellar 4.77% (Vanguard). So make sure you ask for the best rate or transfer your cash to a high-yield money-market fund.

We based our rankings and the commissions we report below on a hypothetical buy-and-hold customer with an account of $50,000 who invests in stocks, bonds and funds and wants to write covered calls. That means our top-ranked site would not be the first choice, say, for a day trader or for someone who buys only mutual funds. Below are our results.

Fidelity
For the fourth year in a row, Fidelity dominated the discount brokers in the premium category. With products ranging from cheap Treasury bond trades to precious-metals storage, Fidelity offers just about everything a penny-pinching trader could want. Customer service was excellent, and we were impressed with detailed responses to e-mailed questions. Fidelity investors have access to the company's 208 mutual funds (and 1,132 others) without a fee, but you'll pay a whopping $75 if you want to buy a fund outside the network. Also, if you have less than $50,000 in your accounts, you'll pay $19.95 to trade instead of $10.95 or less. And though we liked the "hypothetical trade" feature, which allows you to see what effect a trade would have on your asset allocation, we found it difficult to navigate back to the real transaction.

E*Trade
E*Trade is the product of at least 25 acquisitions, and while complaints from people like Keen McHugh show that some clients are not happy with their new broker, much of that griping may stem from resistance to change. There's a lot to like about E*Trade, including its intuitive trading platform and online tools. The cash "optimizer," for example, shows account holders how to reallocate cash to increase interest income and reduce payments. A new planning tool called a risk analyzer helps investors determine if their investment returns are worth the risk and weighs performance against relevant benchmarks. The company recently unveiled unlimited account protection that guarantees you won't lose any money from fraud. Where the firm falls down is customer service — for the second year in a row, we spent more than half an hour holding the line to speak with a customer-service representative. When we e-mailed with a question about money-market yields, E*Trade replied with the answer to an earlier question we'd asked about stock certificates. Lilien, the firm's president, says E*Trade plans to spend an extra $42 million on customer service this year.

Charles Schwab
Over the past year, Schwab took a long-overdue step: The firm finally got rid of its hidden $3 order-handling fees, which were tacked on to the commission of every stock trade. Now customers with $50,000 in assets pay $12.95 per trade (up to 1,000 shares). But mutual fund buyers look out: Some out-of-network funds carry transaction fees as high as $165. With almost 300 branches around the country (versus 110 at Fidelity and 267 at Scottrade), Schwab is a convenient place for banking and meeting with advisers. And despite the firm's discount roots, Schwab claims it can satisfy the full-service needs of the wealthy clients of a Merrill Lynch or UBS. "We're trying to improve and expand our whole business around personal service," Charles Schwab told SmartMoney. The Web site provides top-of-the-line Goldman Sachs research, as well as Schwab's own equity ratings, which rank 3,000 stocks with letter grades: A, B, C, D and F. Using the ratings, Schwab's financial consultants recommend individual stocks, which is a rarity in the discount-brokerage world. (Schwab doesn't rate its own shares, but gives E*Trade a "B.")

Banc of America
For several years, our survey has excluded the discount-brokerage arms of banks, mostly because these brokerages were expensive and bank sites seemed to be more focused on banking than trading. Really, the brokerages were afterthoughts. But now, in the wake of commission wars that have lowered trading costs for the entire industry, a couple of banks have started offering dirt-cheap commissions to investors who have a checking account at the same institution. With Banc of America (yes, the brokerage is spelled with a "c," not a "k"), you can get $10 commissions if you have a checking account, $7 if you have $50,000. Our trades were executed smoothly, thanks to remnants of the old Quick & Reilly brokerage, which was bought by Fleet Bank and then folded into Bank of America. A few things bothered us, such as the fact that some quote screens for stocks don't include the price/earnings ratio. And when we clicked the "help" button for information on limit orders, our search returned an article on investing in fine art. Not something we're looking to trade online.

TD Ameritrade
With its merger with TD Waterhouse, Ameritrade now finds itself in our premium discount-broker category. The two officially combined in April, and the premium features of Waterhouse will be phased in gradually. Ameritrade customers will have access to investing advice from Waterhouse, as well as 100 branch offices around the country, while Waterhouse customers will get a sleeker trading platform and much cheaper commissions. Trading is a breeze because a "snap ticket" at the bottom of the screen allows you to trade from any part of the Web platform.

WellsTrade
When it comes to branches, the discount brokerage units of banks have everybody beat: Bank of America has 5,800 in the U.S., and Wells Fargo, parent of WellsTrade, has 3,180. Like Banc of America, WellsTrade offers $10 trades to anyone with a checking account, and $250,000 in assets at the bank and brokerage qualifies you for 50 free trades a year. The WellsTrade trading platform was easy to navigate, and the only thing missing was online bond trading — you have to call the bond desk. One thing that disturbed us was that it is easy to click your way to the banking section of the Web site by mistake.

Vanguard
Vanguard is the pioneer of low-fee index mutual funds, which are frequently recommended in these pages. But once again, Vanguard brings up the rear of our premium discount category. The reason? The site caters to fund investors, and the company says customers typically don't use the trading platform for anything more than buying a couple of blue-chip stocks to supplement their Vanguard funds. So if that's your investing profile, then this is a fine choice. But if you plan to trade stocks and bonds, the site is unwieldy, and if you want to buy or sell a fund from any other fund family, you'll pay a $35 transaction fee.