I've never been too fond of this game. I like it better than the slot machines (which I pretty much never bothered using), but far less than just buying coins. I've gotten to level 6 or 7 in Voltorb Flip (never to level 8, though), but I've found that there's normally a point at which there's no way to know which tile to pick, so I just have to pick one and hope for the best (and normally, things don't turn out too well).
The game corner prices for prizes have seemed far too high in generation 4 in general, though, so I normally just trade with people for anything I might need and send over some prizes from the third generation game corners.