RE: is a sts really worth its weight?
I have a custom made one on order for my Allegiance. I see the advantages and enough people out there do as well. If I do lose a couple FPS, so what. I'm not too concerned about that. I'm more concerned about the quietness of the bow. I have heard that tnew EDS stopper used by STS, as well as the guy who made mine, is a lot quieter and more flexible. The older version would create a "slapping" noise when the string hit it.
Also, Hoyt started using such a device this year on their bows. I'm not saying Hoyt is the authority on everything, but their engineers seem to do a lot of good work when it comes to bow design. If they use it, that makes me confident enough to think its worthwhile.