Road Redemption has quite many weaknesses and you can read a lot about them in all the other critical reviews.
My main gripe is the repetitiveness though. You might think "That's what some others wrote too, so what?" but I want to assure you how INCREDIBLY repetitive and bland this game is, you have no idea.

Sure, there is a skill tree. It just doesn't matter. At all. Nothing in it will change the game experience.
There are different riders and bikes, those don't matter either. Nothing adds to a new experience.
There are some different type of races, but you'll have seen them all after about 1h.

Just don't bother and buy something else.