Initially a very addicting game. Wonderful loop and catchy music and sound effects. The only critical feedback i can give is that when you get far out into the game and realise you have maxed your damage / radius etc you no longer get those upgrades, and you end up loosing just because at some point you can't kill the asteroids fast enough and there is nothing you can really do about it. It robs that "building for specific strat" feeling.
but other than that i had a blast, got hooked for a solid hour on this, great fun game!