Quoted from metallik:

I had a Congo for a while years and unloaded it for 1500 about 4 years ago. The game is OK but nothing special... just a bunch of disconnected modes with no cohesion. The gorilla toy can be beaten by flailing... the volcano is pretty cool, especially when the tip breaks off and it starts throwing pinballs all over the place. The music is by far the best part of the game. Upgrade the speakers so you get the bass out of the diamond hunt cha-cha.
I predict this game being a passing fad, and it will fade away as people get bored with it and more Stern and JJP games come out. But, who knows. I know I'm done with it.