I can't say I've noticed a difference in lifespan between wethers and stud alpacas.
(They may be a special case of mammal. Alpaca fighting teeth are designed to rip off an opponent's testicles, and the testes are provided with a quick disconnect socket to prevent death by blood loss. Wethers become herd guards and, being front line troops, probably have a decreased lifespan.)
I think I would rather have a heart attack in bed with a hooker tomorrow than continue my deterioration for the extra few years.
