For the record, I bought GTA5, but I got a bunch of nonsense. Part of it probably wasn't Rockstar's fault: Some Russian apparently hacked my Social Club account. Changed the password and set my profile to a Cyrillic "Hello!". Considering I had GTA4 until now, fair enough hehe.
But even after resetting my password, I can't actually download GTA5. The interface is [][]... a piece of shit, that's the moderated version. It claims I own the game, but also that my key has already been redeemed.
They say my key (direct from HumbleBundle) has already been redeemed. But I can't find any way to download the game. I'm not sure if it's "You own the game but you must verify" or "You haven't found the specific page which lets you download your game"
Personally my take is "screw this, I'm enjoying Killer Is Dead (which I paid for, but is still currently free for... I can't tell, probably ~6 hours?)"
GTA5 is fuckin huge on disk space anyway. Largely justified, from what I've heard, but it's still a consideration compared to appreciating less-AAA games. GTA5 can be a good example of triple-A gaming and it still has to compete with godsdamn Spelunky because it turns out content is secondary to mechanics.