I've tried them all. I use different solutions for inlay and hot stamps.
What works best for me for inlay chips is a little Dawn dish washing soap in a bowl of warm water for a few minutes, scrub with soft bristle tooth brush, dry and wipe with cotton cloth with a few drops of clear mineral oil or Pledge Lotion to replace the lost oils and restore the color. For Hot Stamped chips, Pledge Lotion works great w/out removing the gold (even old, worn gold). "Pledge Lotion" is difficult to find-- all stores do not carry it. The Pledge can has to say "LOTION". Do not use regular or any other kind of Pledge.
Allan Myers