I just tuned my 06' Chrome Old Glory Saturday with an STS and no problems for me?..........In fact I can't recall any of my 3D set-ups tuning differently with or without. I can take it off , put it on and still shoot the same pretty bullet holes.

I have no interest in this product as a hunting tool. I shoot higher brace height bows with good form and string slap on anything has never been even a remote issue.
What I use it for is in 3D competition. Even at only 60# any bow generates some snap with light arrows and no string silencers, the STS soaks upany accessory jarring vibration and if it gets the arrow off the string more consistently shot to shot (and quicker) maybe it does help with accuracy to a degree by combating human error at the end of the shot?

I do know that I shoot very well with it on, have no tuning problems to speak of and since it is only used on foam animals I don't sweat an slight change in sound vs. string silencers. I shoot without any in competition so the STS is an improvement in noise for my application.

Would I shoot to the same level without it on my 3D bow?Not sure Iwould even be able to quantify it due to the ever changing variables on a 3D course.........now if I was a spottie who suddenly took it off and instantly noticed a drop in my scoring average that's something else.
In 3D it would be too difficult to attribute a score on one particular accessory.

I'll keep using it, it serves a specific purpose for me and for whatI want it to do it works.