it depends...and these types of transports can get pricey. The Esoteric and dCS transports are likely amongst the best at a cost. Esoteric seems to be one of the few that (used) to make SACD and DVD transports
Also some drives just read the disc into memory..so the transport can be more of a computer grade...
I guess the real question is what are you trying to accomplish? Better sound quality? If so...what's the rest of your digital front end?