If you really like this woman and want to keep seeing her ..... makes sure she nuts first, no matter what, however long that takes. When it comes to her just forget the clock.
Once she nuts it don't matter how long you last afterwards, could be 30 seconds even, she will be content and you will both be happy.
Outside this hobby I've been with woman who can nut very fast (less then 2 min) and some that can take a lot longer (15+ min). How long you last won't matter at that point after she orgasms and she mostly won't be concerned with it. Don't think about it.
I agree with psefreak on this one.
If I get off, 1,2, or 3 times before the hour is up, I'm in a great mood, and look forward to seeing them again.
But how long a gent lasts, isn't an issue for me. Someone cums quick, I take it as a compliment, we can go again, and again if he is able to. If he takes longer, it just means I have a chance to have an O myself while we are at it. What I don't like, is when he purposely interrupts himself preventing his climax (edging) just to last the whole hour. It can prevent his ability to climax in the end because he's tired himself out. Or when someone can, and purposely hold out not to cum for the whole hour. Just straight f*ing no foreplay, is just a boring time, it gets old fast. These are the ones I say a blowup doll, rather than a real woman is what they need. Thankfully that is rather rare though.
I would say 30 minutes or less is a good amount of time. It leaves time to cuddle, chat and go for round 2 if they are able to.
I've even had a 4 year relationship, that he was great at cunnilingus, and would get me off over and over, but when it was his turn, he was a 2 pump and done sort. The little blue pill did help him last longer when he took it though. But is expensive if you don't have the funds to afford it for every night. Didn't bother me. His joy was in pleasing more than being pleased at least.