Absolutely awesome game. I never played a mega-man style platformer where you have to reload and conserve ammo. It is a lot of fun and with the constantly respawning enemies, you need to be careful and plan ahead. The game also looks great and has a fantastic atmosphere.
My one complaint: it's a bit hard. The instant death spikes were a huge penalty and it took a while to go through the Game Over screen. Still, that's a minor complaint overall. This game is super polished, super fun, and really creative!