Re: Unmusical vibrato with Ibanez ZR trems..how to get rid of it?
I own both an Edge-Zero and ZR2 equipped guitar and both react very differently for both down and up bends.
For any given movement of the bar the ZR2 doesn't seem to de-tension the strings anywhere near as much as the Edge Zero does, due to the entire bridge itself having a different pivot point. Of course this helps with accuracy but for really fast pitch changes can be a downside.
In terms of power needed I certainly think the ZR2 needs more for a given pitch change but I can still get crazy pitch changes from mine without ever feeling like I'm spraining any part of my anatomy.
I've used both bridge systems with and without the ZPS: all I can really say is that the ZPS does make it significantly more difficult (in terms of strength needed) to use vibrato, but there again it has fantastic stability. With the ZPS removed though you should be able to pull of any and all crazy vibrato tricks on a ZR2.