I think their business model, if you might call it that, predetermines their answer. This is the sort of thing you can only get from guys who have been in the trenches, so to speak

... Everyone has their own opinions on what ratings are to them.  I've never had ratings that correlated directly with physical looks of the gentleman, I've had gents go on about how great a time they had and give me low (for me) ratings, and get great ratings from gents who didn't say much at all.  It's more important to read the contents of the reviews, than to put much stock in the ratings

I hope you don't mind a non-local opinion on the matter (it it's any consolation, I'm visiting soon).  

Basically, yes, people who are attracted to each other will probably have a better time than those where only one partner (or worse, neither) is interested.  Being only human, I think a provider can have preferences, and yes, I think that this can effect performance.  I also think that great care should be taken in managing that possibility ethically.   If I claim to be a family physician, for example, am I still a professional if I only serve my family members or only those affected by an ailment I like? Or treat someone out of my preference with disdain?  I don't think so, and that's what I think separates -- for lack of better terms -- a civilian from a professional.  I think part of being a professional is superseding one's innate preferences.  

Additionally, I would say nobodysfool2007 in the gentlemen's thread is spot on.  Outer beauty is useless without inner substance.  I think a primary component of what women truly desire in a partner is good personality or manners, and this is especially true between providers and clients.