What are you doing in those 90 min? Chitchat trying to have platonic conversation? 60 min is more than ebough, usually the sp's need a break when i'm done with her, a full 50 min(shower in/out 10 min) of fucking my brains out is enough for both parties. When i met my match i did book 2 hours but i did that only with one sp's that i saw multiple time and we both enjoy the play we did, i did make sure i was her last appointment.
Walk in, small talk, make out, jump in the shower, come out and get back at it. Couple rounds sometimes just one. I had a session where I just couldn't bust no matter what, kept going at it. As well like in another comment I mentioned all of my sessions have run overtime, usually to the 3 hour mark.
Edit: As LC mentioned I like to establish some kind of connection. I've never been the type of guy to rush to fuck a girl, the connection is so much better, so important, its what gets me hard. So while I don't spend 25% of my time with the girls yapping, I repeat with the same two girls as especially with one of them we text daily.