I have had excellent results with Kontact. I use it at least four times a year if not more often. I have not seen any build up.
Contact cleaners/What's good?
What is your favorite contact cleaner/treatment product? I used to use something called Cramolin (which I can no longer find). I replaced the Cramolin with a small bottle of De-Oxit which worked well on the used equipment that I have purchased as well as the outlets. Unfortunately the bottle of De-Oxit was tossed out by accident when we recently cleaned out under the sink and I need a new bottle of something, preferably a one step treatment unless their is a good reason to use one that is multi-step. I had also wanted to try it on tube sockets as well (another piece of used gear) and wonder if this is advised. Thanks.