LOTS of options in this domain, I think many of them are good options. The ones I know about and would suggest:
-- top recommendation is to get something from the Expert Sleepers lineup as those are well regarded and you would get a robust hub/interface to the rest of your studio. It is probably more than you need presently, but kind of "future proofs" your setup some
-- Befaco also offers a good and fairly broad line of selections
-- Polyend Poly 2 is a good option if you need MPE support

Since the cheaper offerings for this function are not that cheap, IMO it makes more sense to spend up a bit and get a more robust module that will last in your setup for years to come.