I have traded through Realfasttrader.com for the past 6 months or so. I'm sure they follow all NASD rules.
I have over $25k in my account, but I have spoke to several people over there over the last 6 months and they are definitely on the up and up. I like them a little better than IB and Cyber (I've used both and several others) because you get a personal contact with realfasttrader. The commission is slightly higher than IB (I pay .01 per share), but the better service is well worth it in my opinion.