IB has a lot going for it unless you want to daytrade on minute charts and go from stock to stock very quickly. Hard to do with them, unless you have a preset list of stocks you want to trade. Looking for things that are hot off of screens and stuff like that and it takes too long to bring everything up and get it ready to place an order. If you are just starting out, though, shouldn't be a problem, just stick to a few stocks on a list. Or futures, whatever you trade.
If you consider lightspeed, check out very thoroughly their ability to stay current in fast markets. From what I have seen, their platform gets behind and goes down, and I know people that have left them for that reason.