What makes one provider "best" in this specific category?  Tightest?  Loosest?  Cleanest?  Least gasseous?  Strongest muscles?  Best looking head and shoulders (from behind)?

Also, is there any better example of providers faking it than moans of pleasure during anal?  I'm reminded of the post last week about not expecting women to act like the actresses in porn, and sometimes I think this falls under that category.

Having said that, I think the best argument for it I've ever seen is pictured below...