Strange game this - on normal difficulty, the enemies sort of stand around not doing much of much. In their defence, soldiers on your own side don't do much of much either. I think it'd be better if they fired alot of bullets at you which are easy to dodge and which only damage a regenerating bar, so you can shrug them off - then they'd appear to be trying to be threats (but you are just that tough) rather than kinda standing around doing nothing. Perhaps they fixed this in the latter Gundam games?
And then you get to the fourth mission of a character and fail over and over again, after about twenty minutes of play. Eventually I took up the two player option, still failed the once but then beat it! Nice to bring in a ringer!
It does have that 'well, I beat you, but I want to one shot you - and your friend, and your friends friend!' to it, as you can level up pilot and Gundam.
I got it for around $20, so it's engaging for that price.