Just for your information, wives also offer 10 min sessions, 5 min sessions.
In 30 min sessions, wives hope you CIM. (Cum In a Minute).
60 minutes sessions offered by wives usually include MSOGs (Multiple Same Old Gratuitous/Grim Stories).
During any session over an hour, you can have wives GFs (Grisly Ferocious Snores).
On a serious note, I have never BOOKED a 15 min session but I have stormed out a couple of times in about 15 minutes but that's a whole new can of worms. I am not a wham bam thank you ma'm guy so 15 min blow n go, pump n dump is not for me.
I believe I have had one 30 min session and a few 45 min ones and even they seem to fly by quick.