I just beat Mission 8 and I have to say that I'm pretty disappointed with this game. At first I thought it was great and a near-classic, but as the game wears on the sluggish controls really begin to take their toll. Like levels 6-8 I basically just found myself sprinting through them as fast as I could and constantly getting tossed about like a ragdoll. The level 8 boss was particularly sadistic by often throwing you in an endless loop of getting run over. And personally, I don't really care for the mechs as they take the games sluggish controls to a new extreme.
When the game sticks to running around on foot fighting hordes of giant insects it's like nothing else out there, but when the focus switches to mechs and pirates it just feels like a clunky (albeit pretty) retread of the much better Zone of the Enders 2. I'm not sorry I rented it because I'd still say it's worth running through once just for all the pretty sights, but I would have been angry had I bought it.