Best overdrive pedal for guitar?

boss turbo overdrive should do it, boss always makes quality stuff you shouldnt be dissapointed with. Also, for sweet natural overdrive try playing some amps at full volume on the clean channel. Lots of amps have unbelievably rich and sweet overdrive but if you cant always play at full volume then you should get a pedal. Go to boss's website and check out their pedals they give sound samples, so that would make it easier for you to find what you want.