Au naturale is a turn-on for me.  

Some women don't feel this way, but don't worry...if the escort's doing her job right, you should be hard before your pants come off, and she probably won't notice you're uncut until after the fact.

As with circumcised men, the issue for most women is cleanliness.  Do your thing with the washcloth, and most of us will be happy to see you again!

I think being extra clean is extremely important, especially when you are uncut.  Being clean is not only about hygiene, it is also about having respect for the person who is going down there.  If a client habitually showed up un-showered and refused my shower before hand, I may not want to continue the relationship.  The thinking that because you are bringing a donation she should be forced to stomach the taste and the smell is a big problem - the donation is not always the main thing.  Mutual respect, however, is necessary.