I use Tufnut for cases that are all marked up with a Sharpie. If no Sharpie no Tufnut. Otherwise I use corn cob treated with NuFinish. I have tried a lot of brass polish additives, Flitz, Lyman, FA and Iosso to name a few. I like NuFinish the best. It cleans very well, puts on a nice shine and leaves absolutely no film or residue. I also run my lubed-up FL sized brass back trough the corn cob and Nufinish to remove the lube.
+1 on the ultrasonic. Small pickle jars work almost as well as beakers. I use "store" brand sugar free lemonade mixed at 50% as a final rinse to stop the action of the vinegar. Most of the brass comes out looking better than unfired, out of the bag stuff.
50% concentrated simple green 50% hot water.
1. Put cases (de-primed) into bucket with liquid.
2. Let sit for 30min.
3. Pour liquid with cases into sink.
4. Rinse with cold water.
5. Dry with heat gun (or hair dryer).
Total time ~ 45min for 500 cases and the best part...
ot residue
no nasty solvents
no junk to clean out (polish medium).