First off, don't like the music. (Personal opinion). Second the tanks aren't even on the ground, they're floating. The tanks don't shoot missiles, they shoot a huge orbs like colored cannon balls. The projectile is too slow to be coming out of a cannon. After about 30 seconds, you'll be soon overwhelmed by enemy tanks. The controls are nice though.
Bottomline: +Nice controls -horrible sound -gameplay is bad -difficulty spike