I've been lurking on this and other review boards for some time, and some of the information I've picked up has really helped me to be more discerning about whom I spend my sessions with and how to get maximum enjoyment from the sessions. I'm not very new to this hobby, nor am I very experienced, but I would be interested in hearing what criteria other guys use to decide to continue with a session (beyond the she got nice tits check).
Personally, the first thing I notice is eye contact. When I first enter the parlour, does the girl make eye contact, or does she stand in the door looking over one of my shoulders or down the hall? My second is flirting. If the SP isn't even sure I'm staying or not, and she's flirting with me... I'm staying. One of my greatest massages started when the SP took my hand and walked me to the room. That really got my motor running, but I haven't had an SP do that since (but I'd feel retarded sticking my hand out and asking the girl to take it).
I find the girls coming on this board and posting to be incredibly sexy. It goes right back to point #2. Its their free time, and they're still playing the game (so to speak).
In all fairness, I should ask those very girls what makes a session good for them? I understand a lot of the basic etiquette, but what do you most want a client to do?