Meh.....
The upgrade system I guess was ok. But the screen was to small for me. I got hit several times because my mouse was stuck at the bottom of the flash screen. The manuevering was horrible. The guns didn't upgrade good enough to even take down tougher ships unless you bought a super power up thing. But even then it doesn't do that well. I really didn't like the whole battery energy thing. Takes away the blasting fun.