I use the edirol hypercvanvas which is the same as the TTS. In a reply to a previous post Peter Gannon said that PG Music balance their midi styles on the Roland sounds which is what the TTS is.

And as its free - see the no brainer post above about getting it with the free download of cakewalk it seems to me the best solution for a soft synth in BIAB

I've also got the coyote and the forte and the TTS sounds are the best - subject to the bug that means one kick drum does not respond to velocity changes but that's easily remedied in the BIAB settings adn I can't hear the difference in a mix