Between this and its competition (at least, on the 360), Mutant Storm, I think I'd hafta give the nod to Mutant Storm. GW is visually more exciting, but after about 45 seconds, the frivolous details fill up 95% of the screen, and you get killed by something hiding behind all the sparklies. At least when I get killed in Mutant Storm, I see exactly why (usually just that split second before it happens), and I don't feel cheated.
Still, for $2.50, that's hard to beat. Mutant Storm is still $10 (800 points) I think.