I expect they're not all that fresh, although I've generally been lucky in that respect. One thing I have noticed however is that by and large escorts taste better than parlour girls. I'm not sure what it is, it's not that they're unclean, it's just a less natural tasting, more rubbery taste. I mentioned this on Prossynet once and got shot down in flames as taking the piss, but it is my genuine experience.
For the record Nicoletta does have the sweetest tasting pussy I've encountered. It is, to quote a fluffy cliché, a real honeypot!