Its all gear within the right side of reason. I wouldnt use all that magic defense gear in a "idle" set tho, unless you have AF2 in wich case you'll cap haste with swiftbelt and loq earing, assuming march and haset-spell. Most magic damage you take has long enough loading time for you to be able to have a magic def macro you can blink in and out off.
I would also suggest trying to maximise enmity in a few slots in order to free up the rest. I'd advocate cerb-mantle (High breath mantle wont allow him to actually use his resentment cape for what its good for, dmg reduction), eris+1, trance belt, storm manopolas if you can get ahold of them and have af2 body. If no Af2 body i would use dusk for hand or feet instead, to get that nice 5 sec recast on blind and dispel.
Generally when i prioritize for rdm tanking i go Fast cast > Damage mitigation > Haste > Enmity > Hp > MP = Magic defense. This is for "idle" gear, what i spend most of my time tanking and casting spells in. It differs a little, i actually only bother to cap haste on utsusemi, on my spells i use enmity in a few haste slots, cause the recast is pretty low as is. And before you wonder why i have mdb so far down is because as i said, you can genereally find time to gearswap for mdb when you see a mob ready a ws or cast a spell.
And yes, i want those shoes.