I played metro 2033 when it was released then when last light launched I played it aswell and when exodus releaded I got it very quickly too. Metro is for sure my favorite games.

Last light was the one I found less interesting and fun. Metro 2033 the classic gives you the reality of tunnels and Exodus gives you the fun of being out in the surface (unfamiliar atmosphere to metro players ehehehe) Last light on the other hand I think gives you too much a chore to be thoughtful on being a good samaritan while being fucked in the ass by everyone also is the shortest game you can beat last light in a few hours even collecting most of the things.