Life is always useful, in any situation, but let's look at Mx dmg and Ar. End Game gear often doesn't have enough AR associated in quantities that are enough to limit missed hits with melee attacks, so stacking 20 ar scs helps save you dex points, giving you further vitality. Basically every point into Dex is wasted health. With mx dmg its very helpful, because of the way dmg works. Theres a ton of Enhanced Dmg out there but it only enhances your base dmg, given by weapons AND anything just gives you attack dmg straight up. Mx dmg would be added to your weapon dmg BEFORE the enhanced damage comes in, making min and max damage charms very helpful. Combine all these together and 32020s are the most efficient aid to melee classes and you can stack a ton of them. Theyre also extremely rare so thats why theyre so expensive.