At first, it should definitely be placed in the "Skill-Avoid" category since despite the bosses there isn't much shooting in this game. You have to be very patient at unlocking some of the achievements and playing because with so many bullets at the time even with changing to lowest quality the game sometimes lags like hell, I even seen few times the "ghost" of my ship in the place in which I was few seconds ago. About the medals: I got (is it supposed to be like this?) the Beating the game medal after beating only 26 levels. I also wonder what the trophies medals are about (achievemenst, ribbons?).
Nevertheless the game itself is challenging and very good. Minus half of a star only because of the the abovementioned lag.