Should I Get This Game or Should I Get Payday: The Heist?

[᠌ ᠌ ᠌᠌ ᠌ ᠌ ᠌ ᠌]

Im deciding whether to buy those two games. I only have a little bit of money left and I can't afford both so im just wondering which one I should get. I know it depends on what i like but it's really hard because I like the look of both games. I also just recently got Garrys Mod yesterday so would buying Portal add any things into Garrys Mod so that I can have fun with Garrys Mod aswell as Portal? Thanks in advance.

[Mark]

I'd suggest getting Portal (or if you have enough money get Portal 2) because it's a very humorous game and even after you complete the game, there's more to come back to if you play the advanced chambers which are very hard, but fun.