As far as cleaners, I have always had good luck with the
Neo-Tac products, such as the liquid-nitro and hook-it. Clean-N-Dull from track seems to really deep clean the surface and pull a lot of stuff out (I don't use it after ever set.. but periodically). For daily cleaning, the powerhouse cleaner works alright... a simple mixture of water:alcohol:simple green does a pretty nice job as well.
As far as reviving (oil extraction), I have a rejuvenator, which does an excellent job of pull stuff out of the ball coverstock. If you don't have acess to one, try the hot water bath (there are multiple posts here with instructions/directions for doing this).
Good luck,
S^2
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