Here is the problem. Some of my reviews are reviews of multiple hour sessions, which is why they contain the whole alphabet of acronyms, not once but two or three times. Since no time length is specified, often guys assume this is what they can expect in a shorter session. Several times now, I've had gentlemen protest that "so-and-so wrote in his review that he popped three time". To which my response, "well yes, but that was a two hour date. You've been here 58 minutes. We aren't starting another round with 2 minutes left".

It would be extremely helpful if alongside appearance, attitude, etc, there was also a category indicting how long the session was.

I completely agree with having a "session length" factoid in any review.  Not only does it provide useful info when reading reviews sessions that sound like multiple hour sessions, it helps get a better sense of the quicky sessions.  

If I like one hour sessions, then the reviews that help me most are ones that I can easily identify as having been based on one hour sessions.  Yes, certainly the time gets expanded, but that is taken care of by adding that "she definitely was not a clock watcher."