I've been using the leeches for several years now. I got a deal on them at a local bow shop that was closing and picked up about 10 sets. I don'tput them on my bow until several weeks before bow season because the sound doesn't matter to me while shooting in the backyard. Once i put a set ini shoot the bow to make sure everything is ok and forget about it. I always serve them in and they usually last the whole season wihtout any problems. If i ever run out i may not use anything anymore because my Bowtech Liberty is pretty darn quiet to begin with.