If we're talking about cleaning pins, here's how I do it. First, you MUST take the cart apart, takes less than 5 seconds to do, and you can get much better results, and you can SEE your results. I use a magic eraser, and rather than use it dry or with water, I use ipa 70% rubbing alcohol to wet it. I get it a good hard scrub till it everything is gold and shiny, then I wipe dry\buff with a paper towel. The magic eraser + alcohol is also great for marker, and if you use goo gone gel, removes that too. Only thing you should worry about is getting too much on edges of labels, other than that stuffs very safe.
I might touch them up with a qtip now and then, but it's just three screws to remove the shell, and you can SEE what needs cleaned that way.