Are they worth it ?

James,they will quiet your bow but as to if it is worth it or not depends on if it is worth the amount of noise reduction vs speed reduction. You've shot a compound for years right? Have you ever put cat whiskers on? In my limited experience with noise reduction cat whiskers are the best if you serve them on. They seem to reduce more if they are served and they don't go whipping off as fast if they are served on. I have tried sims limb savers and a whole wack of string sliencers. One thing to tell you. I don't like the way those other string sliencers whip back into my face!

Ive only used cat's once and that was back in the late 80,-mid 90s.Havent use nothing on my other bows.
So with blox you will lose speed right,but quiet down the crossbow.
I havent shot my Pro Fusion yet,just wondering.

If you do it let us know how they compare. I put limbsavers and their little rubber string quiters on and severed them in ,I really did not intend to leave them on originally but they were about 80 percent efficant and I found when I got every thing located right where it was the quietest they only made about 10 ft per second differance in the arrow speed. Lee