@Prometheus Last I remember, I believe -Emnity gear doesn't count towards idling. It doesn't help in the decay of Emnity while idling. Only on actions. Unless SE changed the mechanics.
While Orison is the more versatile piece, I consider this the superior idle body for whm as it has Enmity-5 and also good to macro for regen if you ever use regen and have the inventory space for it.