I played the first game on pc and thought it was great, one of the few games that I struggled to stop playing. I keep re-installing it but I just can't seem to get sucked into it like I did the first time through, good game though.
I then skipped straight ahead to the 4th game which pulled me right back in. I also find myself able to play that through again and still enjoy it but that's probably because it's so short, I can get through it in a few days (still need to get through it on the harder settings for those xbox achievements).
I am not a fan of the re-spawning enemies (what's the point of chucking a grenade in a room if it fills up with enemies again in a few seconds?) but checkpoints are so common it never gets too frustrating and there's always plenty of cover to hunker down behind if you want to.
It's also great fun on multiplayer, I didn't start playing it online until a week or 2 ago but I still manage to have fun and that's not because I'm a good player (I ain't) it's just the way the multiplayer's designed.
I'd like to pick up the 2nd game, I had a demo and really liked it but I never got around to buying it, maybe now's the time.
