A guy ejaculating only matters when giving a blowjob and wanting to taste his fluids. Well it also matters for pregnancy but most men don't lose their prostate until they are in 'oh my god he's old' age so chances of pregnancy are way the hell down to begin with.
This is rather like the length thing, doesn't fucking matter. If it gets hard and you don't last four hours any women, or men, willing to have sex with a guy who doesn't ejaculate will be happy. Do mention this before it gets to point of actually fucking however, that is a need to know first.