Price isn't the only thing to look at. By far the best trading site out there is cybertrader. If you are an active trader - and that means at least 50 trades a month (I used to trade about 100-150 per month) then you're better off at cybertrader using the tools they have. If you're a technical trader, then you'll want to use their tools and pay the $9.95 per trade.
Here's what you don't know as a trader. How do each of these companies execute trades? Which market makers or floor traders are they using? Also, are you trading options or just stocks? If your trading options (aka gamblin on wallst) you better use someone like cybertrader or you could get screwed on your executions. I've been on both sides before. If the market moves against your order, you're stuck holding the bag, and if it moves in your favor - somehow your order doesn't get executed and the floor traders hold your execution for themselves. Its amazing how the floor traders work your order for their advantage.
Andy
www.ccbill.com
www.cavecreek.net
www.drmnetworks.com