I'm using lint free cloths, and believe it or not, metal polish, if you ever try it, use a product called Flitz, or Blue Magic Metal polish. Just make sure and clean the stem really good before it's smoked to get all the residue off from the polish.
The only reason I'm going this route, is I noticed on reading up about restoring pipes Flitz was used quite often for heavily oxidized Vulcanite stems. Blue Magic isthe same stuff as Flitz, and cheaper.
I tried the Brebbia stem polish at first, but it wasn't making a dent in the oxidation. So I had to go in search of the big guns so to speak.
As for the reamer I'm using it's a Brebbia reaming kit, then I also have a nylon shank brush, and the old stand by pipe cleaners.