okay y'want a 40K hot take from someone who isn't playing or painting, and who wanted to build Eldar back when?
I still like Mk VI armor most. A hounskull bascinet look is unique and tells you that these are knights, *kinda* - Mk VII is just a predictable stormtrooper hat. It's not a reason I'm actually thinking about going back to painting but I am *really* happy that Mk X is a more obvious visor.
oh wow, the 40K Wiki actually has a big section about running around with your helmet off.