Have done 2 batches. (50) .460 Wby as fired. primers still in, and (40) .460's after manually decapping them. I wanted to clean the fairly grungy hulls before sizing and prepping them. After 1 hr both batches were nice, after 2 hrs better inside, after 3 hrs they looked like new on the outside. The insides weren't all bright, but all residue was gone. Primer pockets were also residue-free, but I use the pocket cleaner of the RCBS Caseprep anyway while I'm chamfering the mouth of the cases. Now that the cases are really clean, in the future I will resize/decap before tumbling. That will end up saving a couple of steps.
Another thread on this board asked about drying. Since the Sidewinder tub is entirely plastic, I set it on its back in the kitchen sink and rinse everything in it with flowing cold water until all suds are gone, then swish the cases one at a time mouth down in the clear water in the tumbler to get all the pins to drop out, take them out and lay them on a bath towel and roll them around, then blow the pockets and interiors with compressed air and stand them up in wooden loading blocks to finish drying. I haven't had any pins stay in the cases. I don't know how long it takes to tarnish, but so far they haven't. I ended up using less than a 1/2 tsp of the Lemishine, so maybe they won't tarnish at all.
The Sidewinder isn't ideal, but I had it, and it does O.K. It will only take about 3 lbs of the pins, a quart of water, and 50 big hulls. Any more and the tub tries to climb off the drive shafts unless I prop the back end up to make it near level. Suds come out of the vent hole in the center of the cap, but the cap doesn't leak.
I intended to just use the STM system for cleaning big, dirty cases, but I like the results enough to use it on everything I can. It gets cases cleaner than anything else I've ever used. I did read some posts where the pins hang up in 6.5 mm cases and smaller though.
Works for me. Tom
