It depends on what I'm using the rifle/scope combo for. 50 yard parallax is fine for a hunting rifle since I most likely take shots farther than that. On my target rifle, I want an adjustable objective.
PERFECT ANSWER !
Most shooters won't NOTICE the difference either way. If they're trying to shoot one hole groups and and have a wanderer or two they think it's just them (it is). You're average rimfire shooter doesn't take the time to test ammo brands and tend to shoot the cheapest ammo the can find on that trip to the store.