Class(es) that get most/least mileage from BiS

[commongood]

Like the title says, which classes do you think benefit most from "BiS" end game gear. Looking at my necro I can see that of course it would be beneficial to my character, be that while raiding or otherwise, to have an additional 7-900 mana/hp but it actually feels like it equates to not that much. It's maybe 2 extra twitches I could fire off during a hard encounter. Of course resists help to survive AoEs but still... being a purecaster it just doesn't feel that impactful. More of a prestige thing.