IMO, string suppressors don’t hinder a bows performance one bit, if anything they help it. While they have little to no effect at all on the speed of your bow they will help with the forgiveness and the noice.
They stop your string from ociliating which in turn causes your arrow to be released from the string ealrier. This gives the shooter more forgiveness since the arrow leaves the string faster and can’t be affected as much by torquing your wrist or dropping your arm. They also reduce shock and makes the bow quiter. Although the forgiveness may be a small increase, anything will help when that moment of truth comes.
This is just my opinion and what i’ve noticed with them. I have one on my general and my dxt and will put one on the rest of my bows. I love them