Rush Bros is a pretty addicting race platformer, which lets you race against friends or other people on the internet. It is challenging, but far from impossible.
First of, this game has a main gimmick: music. You can import your own music into this game or just play one of the music within the game as background music for the stage. The fun thing is that Rush Bros applies your music to the stage. Some obstacles, including spikes and pillars, go along with the beat of your song. That means that it can be used in your advantage or in your disadventage. When you are playing online though, the opponent has his own music, and therefore also his own obstacles.
As I've said before, Rush Bros is a challenging game. But that is mainly for the achievement hunters or the competitive online players. Whenever you die, you respawn just before the point of death. You have infinite lives, so you don't have to worry about dieing. This also goes for online play.
Me, being a speedrunner, absolutely love the stage designs and eventually reach the goal as fast as possible. I myself do not care much for achievements, but it's a nice aim nonetheless.
However, this game is mainly for online play. If you don't have anyone to play with, this game is less fun than it is supposed to be. Also, you might want to use a controller, as it is clearly not made for keyboard use.
Rush bros is a fun and entertaining game, but I would advice buying this game when it is on sale. Otherwise, it is not worth it.