I’ve got a Brass block on one of my Charvels, and a Titanium on another(off eBay for 70 bucks). Titanium string blocks too. They do make each guitar more resonant; brass being darker/warmer. My vintage Jackson, seems to be perfect with the stock block. They improve a thinner sounding guitar for sure.
I didn't know that either. Have one that came with my MIJ Wolfgang. Love the guitar so it must be working. None of my myriad of other Floyd guitars have them.