The best I have found is the BowJax crossbow silencing kit. Includes two limb dampeners, four string dampeners and and a retention spring dampener.
My Excalibur had some of the vibration reduced with the kit in place. Still loud but better than it was.
With the Excaliburs the spring dampener will not fit because the spring is so close to the arrow. I do plan to buy a few more of the limb dampeners and put them on the barrel of the bow instead of the limbs. Too much on the limbs or string can slow it down.
I support all hunters, regardless of weapon or technique!
a crossbow is going to be loud, because the sping is comming to a complete stop a loooot faster than a compound. and by the time the deer looks up to hear the crossbow snap, he or she will already be breathing their last breaths.
Should I shoot? I don't care, im not the one holding the gun, if it was me, we'd be skinning by now.
There are a few items coming for 2011. I gave limbsaver a few ideas at the ATA show last year and they have been working on them all year. They will have a kit available very shortly. The bowjax kit is good as well. There will also be many new string stoppers available in 2011 too. Parker is making them available for thier whole line of bows and Excalibur is probably going to make them avialable also.
Most of the noise/vibration you hear/feel is coming off the foot stirrup and the arrow retention spring. String stoppers help a bunch too. I don't like to put anything in the string.