I have used Teflon patches for about three years now in some of my rifles and does work great and have yet to find any warts. I know alot of other shooters who use the stuff also and have had heard nothing but good to say about the performance of the stuff. I have been told that the stuff can cause problems if not handled properly, as in try not to injest any when you break for lunch, etc. Drinking, smokeing, too much fatty food, and a host of other things will give you problems too so caution and care in use might be the by word with using teflon. Smylee