ALL sex sounds and voice overs are USUALLY horrific and crap. Just pure manure.
So I'm glad they didn't put in on anything where any MC is involved.
NO ONE should ever put that in their games. Porn actors are NOT known for their acting skills, not even their realistic moaning (If you believe porn you're simply put: A humongous moron!).
For VA it depends on whether they're also a good voice actor or not.
For example, LT runs the gamut in terms of its voice acting. Ranging from really good (Zoe, Megan, Sophie etc. With VA's that are great both for the sex scenes, but also just for normal story content as well) to the really bad (Amy's mother, some other smaller characters). There's a clear dissonance between those who sound like they're phoning in their dialogue, versus those who are quite possibly using the renders as a basis to determine how to voice the line in question. There's a clear dissonance between those who are clearly changing their voice to sound happy or angry or sad, versus those who are just reading lines.
I like VA in games, but I also don't think all games need it, and I'd prefer if there was a standard for the voice acting, which is not always the case sometimes. Given that Inceton only voice their female characters, there's a severe lack of females in this game lol. Hell, Inside Jennifer still only has Jennifer voiced, and that's the only other game besides LT that has voice acting by Inceton.
But hey, that's just me. Do I think this game needs VA? It wouldn't save the game but I wouldn't be against it. I'd prefer those resources go towards something else though.