ok, who here has aluminum or iron diff mounts? or even engine mounts

i was thinking now that I'm replacing my broken diff with a kaaz unit, might as well upgrade diff mounts, thinking of making my own of aluminum or iron but would like some feedback from people who has them in their cars.

and also would like some real first hand experience in a fd rotary car solid iron or aluminum engine mounts?

any REAL first hand experience.

how bad is the vibration?