Boring
There isn't a whole lot to this game. The controls are simplistic; the various obstacles can be counted on one hand; there are only 9 upgrades, and none of them is all that great. The achievement and scoring system is well-made, but in the sense that it feels like you put more effort into that than into the game itself. I've played this game for about 20 minutes and feel like I've done everything there is to do, even though I still have one ship to unlock and Scorelord to complete. Frankly, there just isn't enough variation to keep me interested.
Some people have pointed this out before, but just in case you haven't heard; space marine and golden oldie appear to have their oxygen capacities switched.