it takes me 56 minutes to cum..so an hour is just right..

There are a couple of providers I see for whom no amount of time could ever be too much because of the emotional factor, the intimacy that they deliver.  Somewhat recently spent four hours with one when I only had her booked for far less (or course she was compensated) so I guess it depends on what you are after.  Also had my first overnight recently, but that is far less costly in the other area where I hobby than here.

I couldn't fuck Mila Kunis for two hours and she is the ultimate hotty for me, not at this age bud.  But if there is something else every bit as nice as the sex that the lady is providing , then that extra time is well worth the investment.

All that said, the hour is always a great idea for a first experience with a women.  

My 2C.

Some, I will need more, depending on the activity. Some, I will just need one hour. Sometimes my schedule is too busy, and all I need is one hour for a satisfying time.

Here is the quick summary:

Some agency girls and indies will leave you completely satisfied within that hour. Really, will blow your mind in that one hour. Like, leave you drained. Depending on what I do. If I need some fantastic mind blowing sex, then I know who to hook up with.  

If I want to do a dinner date, hang out, or something of that nature, then I'll book more time. Usually one hour is plenty enough for me. Actually, depending on who you see and it will always be YMMV, and especially with indies, they will allow you more time afterwards. I can't emphasize how many times I have went over the hour mark with me taking a girl to dinner, talking in bed, or hanging out for an hour or few after I paid for only ONE hour. Again, its how you connect with these girls and it will ALWAYS be YMMV.

I can sometimes manage two cups in one hour. However, usually I will just go for one and prolong the fantastic intercourse if I pace myself. You said, "I can't see an hour being enough time ever." And I say, it depends on what you do as mentioned above.

YMMV is the applicable term, here- sometimes a half an hour is perfect, sometimes an hour is too long, and you was wanna handle your biological imperative and roll out, even if the girl is gorgeous and accommodating- chemistry is first and foremost, at least it is to me- if I really dig you, not only will I pay to stay longer, but I'll do "extra" stuff that costs me money (work wise)

for me.

I used to think I would start with 1 hr appt then next time 2hr., next 3 etc. but now I think the other way around is better. Problems could arise either way but as someone mentioned YMMV. One lady I saw who was well reviewed would have been torture to stay for another hour. Only saw her once.lol. Another I booked 1 hour and wish it would have been 3.