Airsoft all the way. When I was younger I wanted to get into paintball, but when I discovered airsoft I was hooked. My buddy is actually into paintball but I'm not sure what aspect of it. His markers are shaped in the form of an MP5k and an M4. Not bad actually, looks close enough. I asked him why he didn't get into airsoft and he told me because with paintball, whenever he gets the itch to play he can just head to the local field and start shooting. Doesn't have to wait for games to show up on the boards for local stuff etc.
To that end I agree. Paintball if you have an itch to shoot somebody and you can just go with your friends for a night and have fun, but thats just to settle. Airsoft all the way.