They'll be direct ports of the SACD titles, so they'll sound exactly the same.
I actually quite like the Genesis SACDs, but their workflow for making these was just stupid from an audio purity point of view. It went something like this:
Original analog multitracks -> digitized at 192kHz/24bit PCM -> mixed in ProTools at 192/24 -> 5.1 mix outputted to DSD workstation for SACDs -> converted back to PCM for the DTS and Dolby Digital tracks on the DVD-Vs (and now BluRays)
(Source interview
here)
So what you're listening to is something that went analog->PCM->DSD->PCM->your ears. You can argue the relative merits of DSD vs. PCM until the cows come home, but when something is a bit of both, no one wins and I think everyone would agree on that. To me that's inexcusable, effectively you're listening to a 3rd generation digital dub simply because a multi-billion dollar company couldn't design a simple digital workflow or do any type of forward thinking asset management.