I got it when it was on sale by 90%. The game is a piece of cake. I won my first race by tuning the handling and acceleration with a 3 star team in addition to buying all the top notch supplies.
The game can be a challenge if you handicap yourself, but otherwise, not really. It only gets easier and easier as you get sponsors, and as long as you win races, you can replace your parts very easily. Some parts get worn out to 50% after one race, but they cost less than 25-50k while winning a race gets you 1m. If you have two drivers, that can go up to 1.9m, and there are lots of free agents at the start to hire mad cheap. My salaries were 50k even though it said a 20k salary would guarantee a contract signing. It's very easy to hire personnel as well. You just have to make sure you're balanced.
For $2, it's worth it. For $20? Nuh uh.