No, but I try to make a mental note of objective data. (e.g. her breasts can be sagging, firm, stretch-marked, bouncy; they are not delicious, horrible, juicy, amazing). I keep track of the time she starts and finishs for my own benefit. Things like that.
There's a 'global' (or near global) benchmark that is slightly better than purely subjective. For instance, Charlize Theron is "very good looking" (which is different from saying she is a model, which she is as well) and Kathy Bates is (physically) "rather unattractive." On this scale, most prostitutes are average, ugly or "good looking for a whore" but not "one of the most beautiful women I've ever seen" or "perfect".
The reason I don't include subjective data or the idea of a rating at the time of the punt is because I'm doing my best to enjoy it. I'll get a clearer idea of how enjoyable it was, and how enjoyable she made it, on my way home. And probably an even clearer idea the next day when I'm not thinking "I've just paid £xx for that!" (paying a lot of money encourages us to think better of something). I'll get a better idea still when my balls are back to normal, I look at her and other girls on a 'see again' hotlist, and compare her looks and service and vfm to overall doables.
