This is my opinion on the STS. $45? look at it, maybe cost 5 bucks to make. These people are making a killing. Price is way to high for what you get. I have not seen all of the positive results that others have seen. Don't know why but I'm not. I have a hunch that this system will work better on reflexed riser bows. Simply because the arrow is gone from the string sooner. I see no improvement with a Protec, but on a turbotec it made a big difference. Just what I have noticed.