They will outlast regular silencers, and as an added benefit, they keep the string at brace height after the shot, eliminting the need for an arm gaurd.
Exactly. And... as an added benefit, I like the fact that I can remove whatever hush kit or leeches is on the string and have nothing but my tied-in nocksets, d-loop and peep on the string -- and I feel I am JUST as quiet as I am with leeches on the string.
I got a brand new '08 Guardian in a few days ago, and the first thing I did before even setting it up was to screw in the MeanV suppressor I had just got in for it and cut off the hush kit on the string. Super-quiet, and picked up a foot or two per second in the process.