This game is the worst in the series. For one simple reason. I get to the Koyakk or whatever boss, the one on the first planet you're sent to on your own after getting the missile upgrades. I shoot him in the mouth, then hit his belly like it says. Energy charge shots useless, pummelling is useless, missles are useless, the ultra damage PED mode is useless. I wasted 30 minutes attacking this thing and his health bar moved maybe 1/32th from where it was. It wasn't even CLOSE to 1/4th. I know I was hurting him, but it was moving extremely extremely slowly.
When game developers resort to this lame tactic this early in the game, I'm sorry I'm not interested in any other part of the game. The other reviewers here are lying or used cheats to get past but I won't do it. Sad for the Metroid series, but I'm done with it as this was a filler title before I sell my Wii off. This is also the first real game on the Wii I've played and may I say the controller is terribly uncomfortable and left my arm in more discomfort than a keyboard and mouse or standard game control ever have.
I wouldn't recommend this game for anything, simply terrible. When developers resort to insane tactics to make a game completely unfun, I will never play anything else from them. Bye bye Metroid series, it was nice knowing you. The same recycled formula from the first and second Metroid Prime games is way past due and I don't think they'll change it anytime soon. Again, done with Metroid now and forever.