I wouldn't say there's any "bad" creatines, just bad genetics (or, heaven forbid, other variables).
Some people will tell you good ol' Monohydrate and juice is all you need. Some will tell you CEE is where it's at. Some people will only buy a kitchen sink blend (NO Xplode, Swole, V-12, etc.) While others still will tell you that all creatine is crap. (And let's not forget those who think it's a steroid, despite the fact that -ine suggests an amine)