Over the last few months I finished both 3 and 4 and loved them both; 4 was full of call backs to the first game and I'm finding myself wanting to play it but it seems to be fairly rare/hard to find, is it worth seeking out?
Gamestop has it used for $13, which isn't a terrible price but i remember thinking it felt like a kinda messed up GTA clone for next gen when i rented it. It wasn't terrible but it had its share of problems, and i got bored of most of the stuff in the game about halfway though but still managed to plow though the main story just to see where it went (i do remember enjoying the characters and story). Makes me wish it was downloadable for $5 after playing SR4, just to mess around and refresh my memory. It had its moments but like everyone else said it was far more serious compared to the other games and didn't have the same charm.