I'm circumcised and 99.9% of the blowjobs I've received were part of foreplay, so me cumming wasn't the intent! For the very rare times a blowjob to completion was the endgame, I've had no trouble at all cumming in those circumstances. How long I last(ed) really depends on the skill and technique the woman is using. If the woman is using her hand, or both hands, while using her mouth on the head, and being quite enthusiastic, I can cum in a few minutes. If she can go deep (like my wife) that sensation is amazing, so how long I last depends on how often she goes deep.
Amazing! Where did you find this? I need to see more of this extremely talented woman!