Watch that double posting, you don't want the admins or mods in your back
I don't know why the hell does people keep comparing Metroid Prime with other FPS games... well, I have just answered myself, because most of people think of MP as a FPS when it's a FPA, and there's a huge difference right there.
HALO owns Doom big time, but then it'd be hard to make a comparisson between HALO and Prime.
Both are absolutely awsome games on their own rights, both have given me a good challenge and both have been as fun as hell.