I usually take 20 minutes anyway and tell the girls that I'm happy to pay extra if it takes significantly longer. The ones I visit never make a fuss, and a nice foreplay with cuddling, followed by one or two positions, is easily manageable. And if I ran over by five minutes, it was never an issue. Stopwatches don't run anyway, and there's usually some gossiping at the end anyway.
I don't need a marathon fuck with 10 positions; I'm pretty simple in that regard. Of course, I (and most girls) don't like banging either.
And I don't "test" new girls with 30 minutes or more right away. If they're willing to go for a quickie, I'm happy to go longer, and perhaps even regular visits.
The Giulia, for example, drove me into the ground in 15 minutes, so that even 10 minutes would have been enough in the end