I have two occasions when l have brought a guy off quickly. First one was a married guy who l had lusted over for a few years, his wife used to send him in to pick up her work, to cut a long story short he wanted a job doing and got him into the office one Saturday morning when no one else was there, we had already skirted around subject of blow jobs and wanting to get fucked, i had said i would swap this one job for 'payment in kind' he smiled, took us ten minutes to do the job, i had been rubbing his knees while he was near me, i put my hand on his crotch and he was rock hard, i pulled his pants down and i bet he lasted about 30 seconds !
Second time was a guy from the gym l had lusted over as he used to strut around in some very skimpy shorts, he taught zumba classes. Roll forward a good number of years and i got an email out of the blue from him (I had done couple of adverts for him over the years), we got chatting on WhatsApp and the conversation soon turned raunchy as said he liked older guys ! About a week later we meet up and have a snog, i pull his zip down and go down on him and again well within a minute he cums !!
Sadly I can't say they are all as good as these though !