They have very good quote/platform reliability {TradeMaven or their own platform} and you can usually negotiate a decent starting rate roundtrip. i currently use them for some of my futures trading and i am very pleased. i will also pass on that i have always had exceptional customer service dealings with this company --- that is very important imo.
If you call, ask for David Truffleman, he is a trader and posts on this board as TRUFF.
I remember looking at Flash, but (if I remember right) they had some high intraday margins. And they didn't post any commission rates on their site, you had to fill out a form to get them.