I think the problem is that everything is dimly lit so its hard to estimate the age. Besides, we as guys don’t spend to much time looking at their faces the first time we are there. It wasn’t until a third time I was with one girl that I could tell she was closer to 45 than the 30 which I estimated. To really gauge their age, ask them to turn on the lights because you can’t see when you are getting dressed. But, you may be disappointed in what you see.
I’ve learned now that the age does not matter. I’ve been with girls that were 19-60 and the ones that were under 25 were horrible. For some reason 35-45 is the sweet spot. As long as you leave satisfied and want to come back for more, who cares about their age.