I highly doubt V's PC version will be anything like IV's.
IV was their first time making a GTA game on their new engine. IV's PC port was the first time bringing their new engine to the PC. The performance on Patch 1.0.4.0 was a lot better than the game's original release.
Then they went on to make Max Payne 3 for the PC, which went to show that they have gotten a lot better at getting the Rockstar Advanced Gaming Engine to work on the PC. MP3's PC version was also developed alongside the console versions.
There are buglogs for GTA V that indicate the PC version was most likely in development during the PS360 versions, with the PC and DX11 being mentioned multiple times in said logs during the same time the PS360 versions were being tested.
It's also worth mentioning that GTA IV's port was done by Rockstar Toronto, instead of Rockstar North like they usually did. The guys who did MP3's PC version (Rockstar Vancouver) merged with Rockstar Toronto at some point. So whether North or Toronto developed the PC version, it isn't going to be the mess that IV was.
And with all the hype they're trying to build for the performance and visuals, and the delays that were meant to "polish the game" (except the last delay, which was most likely to push the game's release into the next Quarter, but they won't admit that) - they'd be practically committing Self Delete if the game is as bad or worse than IV's port.
So I don't know. I guess things are looking pretty hopeful for GTA V's PC release.
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