I regularly wank while watching Lynn getting fucked but I always try to hold off cumming until after whoever is enjoying her is done with her even if that involves several rounds of cleaning up which it can do with more than one guy.
I find it much more enjoyable taking my turn with her after they’ve finished than losing my load before the shows over.
Easier said than done I know and in the early days with my first wife, I’d regularly lose it when a guy was cumming in her. Hell the first time I watched her fucked, I came just watching him enter her.
It does become easier with experience to hold off cumming and it is worth it to be able to enjoy sliding into your wife’s freshly used cunt or ass. That feeling of entering her hot, slick, used hole is so much better than just jerking off watching. You can jerk off anytime reliving the experience in your mind but it’s such a wasted opportunity not to fuck your wife after you’ve watched another guy or guys taking her.