Pretty good game. However, this is a real grinder.
A couple critical points:
It's almost impossible to complete this game in a reasonable amount of time without purchasing skulls.
There tends to be an increasing amount of slowdown in the game the longer you play the game.
It's a solid game. I've been spoiled by all the games like this on Kong though. Enjoyed the introduction and the first few levels. Time to look for something new!