Dropping item levels for tier?

[Resshin]

It is definitely worth dropping 685 mythic Highmaul gear for two/four piece, right? I am mainly asking for fire/arcane.

[Komma]

Disclaimer: Completely biased thoughts after messing around with sims. No evidence backing at all. Assuming you're talking about heroic 680 tier:

Fire 2T17: Probably yes.
Fire 4T17: Maaaaybe yes. I probably won't.
Arcane 2T17: Probably no.
Arcane 4T17: Probably yes.

EDIT: This is considering 6.1 with the Fire 4T17 nerf. The pre-nerf version is definitely worth giving up mythic pieces for, especially poorly itemized slots.

[DJG]

This results are similar to mine, so yes it is worth droping Mythic HM ilvl for set.
And for Fire 4pc is better then arcane 4pc.

[Valounette]

I have mythic highmaul 685 legs and chest... and it was a gain to replace them with NORMAL set pieces (665 and 671 wf) when simming for Arcane. 300 DPS increase.

After simming, I hit dummies for a couple of hours and see no noticable difference between the mythic highmaul or normal-2set in DPS.

Didn't sim for Fire, but the practicality of having 2 Inferno Blast charges seems very much worth it for squeezing in extra Living Bomb spreads on many fights

[Wilderness]

My gloves are still heroic, but the other 4 slots are all Mythic; I'm about 680 ilvl overall. I swapped in gloves/legs for the 2-piece sets, and shoulders were my off-set piece for the 4-piece sets. These are my results from what I ran today: 300 second length, light movement settings. Arcane was SN/RoP/PC; Fire was LB/IF/Met:

Arcane: Single-target


Fire: Single-target


Fire: 2-targets