Never used a brass bloc before, but I always wanted to try, as there is a lot of talk about the advantages of brass block over the stock blocks on floyds. I used it on a Schaller floyd from a Charvel Pro-Mod So-Cal, alder body and maple fretboard. The sound was way too bright and lacked low end.
The effect was quite dramatic. It did improve everything. The sound is fuller, there is more bass, significantly more sustain and the overall tone is still bright but more powerfull, no more glassy/ scratchy type of vibe.
So, I will upgrade ALL of my floyd rose guitars with the brass block.
I really recommend it. At least try it out once!