Ok, I've played it quite a bit more. Still loving it and made it to number one in stage one leader board
The only problem I can see at the moment is that the coins you collect seem a little useless. You don't keep them at the end therefore you can't spend them on anything like upgrades. You do pay for the bombs you use as you go along but they are really cheap so you don't really need to collect any coins after the first 30 seconds or so. I worry this may result in a short lived attention span for this game.
Well worth the asking price though.