This game is a great GBA side scroller shooter, I am not sure what you people were expecting. Obviously the NEOGEO versions are better, of course they are. But for the handheld this game is great, much better then contra that was released. Now all we need is a good GBA version of Gunstar heroes.
What I like most about this game is, it definately keeps the feel of arcade Slugs, I too wish SNK/Playmore used more space and added more, but maybe they will make a sequal. I think overall this is a great game, that doesn't feel like some old Amiga platformer or something.
Compare it to that other Metal slug rip off on GBA, I forget the name of it, this is so far ahead of other side scrolling shooters on GBA, and I don't think they even gave it their best shot, hope the game does well and they make another!