I'd say velocity and X-trader if you're doing stricltly futures, Rediplus a.k.a. Goldman is more of an equity platform, though has multi-asset capabilities, Bright and a lot of hedgies use it but I can't comment really on it.
I've used both Redi and TT, and I would have to say that TT is clearly the winner when it comes to futures. not knocking Redi, but I think that Redi's primary strength is in equities and options EXECUTION (not option analytics). TT is your best bet for futures execution. my 0.02