Absolutely a gotta have for me.
When I switched from JEM's to Wolfgangs over 10 years ago, it was a little bit troubling getting used to it, but now I'd never go back. Tuning stability in changing environments on the road, drop D instantaneously, (in the middle of a song), and vastly improved tone. You give up flutter effects and the small pull up range.
You can do it on a recessed if there is enough room behind the bridge. Peavey USA Standard Wolfgangs are recessed.
Block the bridge at the trem block with a glued in, good fitting hard wood block.
Pretty easy mod.