I've just ordered a TI2 KB. Man, do I feel guilty
Okay, here's the first hand answer:
YES, the patches sound different. They lack a little punch and a little crispiness when compared 1:1 to the same patches on a KB.
BUT: The KB has no equalizer, the TI2 has.
So I gave the patches on the TI2 a little bottom and high boost, and ... WOOM!!! they sounded as they were on the KB.
It's a lot of work if you will have to edit EQs on all your patches (provided you program yourself, teehee)
But the TI2 can deliver any brutalness and earbleeding you might ever want. It does not sound thinner, more plasticy, digitally or whatever. It sounds as PHAT as you want.
So yes it's 100% compatible, only with the EQ toned down.
Cheers,
Barely