After reading about the S-coil I decided to go out and purchase one.I got the larger 4.9 oz version. I've been happy with other Limb Saver products, so I felt good about this purchase.
I have never put a stabilizer on my Mathews SQ2 as I haveliked the way it shot with the brass weight in the bottom dampner and the aluminum in the top. ThusI was curious as to it's effects.
When I got home I talked my wife into going with me to shoot. I had her stand about 15 feet to the right of me with her back to me. I shot 10 arrows at the target, some with the S-coil on and some with it off (in random order). I could tell a difference in the sound (quieter) with the S-coil on, but at 15 feet she could not tell a difference between any of the shots, so if you are looking to quiet your bow I'm not sure if it is worth it, at least regarding human ears at 5 yards. Perhaps a deer at 30 would be different though I doubt it would make enough of a difference that it would mean jumping the string or not.
It did absorb some hand shock and on other bows this might be very important, but again my Mathews is pretty darn good as is.
Additionally as mentioned in other posts, for it to work as a true stabilizer it needs to be longer and probably heavier.
I think I'll play around with it for a few days, but in the end I have a gut feeling I'll be returning it and using my money for something else. Nothing against the S-coil (or other stabilizers I've tried) but for my bow going without one feels just as good as with one. My $.02