Hi Rikki
As I said I bought the DGX primarily to use for practice at home as a piano so the limited style endings and variations are not a problem.
The keyboard has USB connection but not a standard midi connector. Certainly one can download from the laptop into the Smart Media card.
The sounds, to me, through my system are virtually indistinguishable from those of the Tyros but I have only tried it at "domestic" volume for obvious reasons.
Sounds, as we all know are subjective and I can only say that IMHO the Pianos on the DGX
knock the Casios into a cocked hat as we old Limeys say.
All the best
Trevor