I'm 99% sure zecco is just $4.50 a trade reguardless of if its a penny stock. I've never used them but they are tempting with their low fees and if you have 25k you get 10 free trades a month. If you really like ST Elite then you would probably be best keeping a little in Scotttrade so you can keep the tools but put most of your money in zecco to trade with. If you like all the bells and whistles TDA with the Think or swim platform is best. The 500 free trades is a ton but I'm using it to just scalp a quick $50 when something on my watchlist is near its low of the day. Trading in a zero-sum game is much easier! here is a quick video of the blackberry app istockmanager for TDA, its a really cool app with live streaming quotes, news, charts, trading, L2 (if you subscribe to it on tda)...its a tda app and they have no account min. requirements so you may be able to just download it without a funded account.
http://www.istockmanager.com/videos