You bought this game solely for the TF2 unlocks.
Don't lie, I did too.
However, the gameplay is actually pretty solid, and addicting. The character interactions can be golden, especially if you pick up on the minute references in the dialogue.
The graphics do have some issues, with chips, cards and other objects failing to track the players' hands (namely the Heavy). There are also occasional issues when a hand ends and the characters' are in a conversation.
However, these really are just nitpicks. The game is fun, and that's what matters really.
From this game I learned how to play poker, which, while not the most useful skill, still makes you look clever.
Was it worth $5? Absolutely. Would I recommend you buy it for the unlocks alone? Sure. However, if you do, be warned; you will fall in love with this game. Just a general heads-up.