1 is an 8/10 on console, 5-6/10 on pc. Godawful port.
2 is a 10/10 on consoles (without non-story DLC), 8/10 on pc (nothing wrong with the port but it comes with all the non-story DLC pre-unlocked which is game-breakingly powerful and the story DLC isn't available). Probably my favorite game ever, and I think there's a mod to disable all the DLC suits/weapons but like I said, they just ruin the challenge/pacing.
3 was an 7-8/10 on consoles, I guess a 7.5 for me, haven't played the pc version but I doubt there's any difference since I saw the DLC on the origin page last night after redeeming my humble bundle code. Not really anything wrong with the game but honestly I didn't want Dead Space 3, I wanted Dead Space 2 2. The MP campaign sounds like it would bump it up to a solid 8 for me but I don't have anyone to play it with so that's right out.
Every time I try to go where I really wanna be it's already where I am, 'cuz I'm already there XBL, PSN, Steam, Origin, BSN, GFAQs, MC: PhilOnDez