The closed circuit race tracks do not gel well with the gameplay
P.A.M. sounds like a really great idea, being in essence Mario Kart but with more gruesome weapons. The main flaw is that the scoring is determined with the amount of kills you get, and even though race position is being accounted for, it has no affect on the scoring (which determines race winner). Because of this, I don't think a closed circuit race track is the best way to go about gameplay, and it gets very stale quickly because racing is not incorporated even though you feel like it should be.
There are 3 different powerups for attacks; front attack, side attack, and rear attack. I found that it is best to get ahead of all your enemies and constantly lay down rear attacks, which can be devastating. Then, while your enemies are respawning, you have to idle or slow down your vehicle, so that your rear attacks will not expire before they drive into them again. This can get very repetitive, and will probably lose its charm on the 3rd of 4th race. Side attack is not as useful, and front attack is best used to get anyone who overtakes you.
I am not sure how multiplayer works, because I have never been able to find a game when I have tried. I assume it is a form or matchmaking but I am not completely sure.
The trailer really oversells this game, so if you are thinking about buying it, I strongly advise to watch a few youtube gameplay videos first, to get a more realistic sense of how the game is.