Thanks to all for the insights. I too, use a vibratory tumbler (Cabela's) with corn-cob media and a little brass polish in the mix. It seems to work very well but I have occasionally had to clear media from the flash holes when I clean after decapping. I use a quick shot from a can of compressed air. It is a pain, though. I hadn't heard about stainless steel media, I'll have to research that. What does it do to the paint on the inside of the tumbler (if the Thumler has that)?
I've used mostly CCI primers but they are still in short supply locally with a limit of 200 per purchase. I've been able to buy full boxes of 1000 Remington primers (large) and Winchester (small) recently. For a while, I couldn't find .45 ACP 230-grain plated boolits either, but they seem to be coming back strong.
I also hadn't heard about tapered pockets in the S&B brass. A lot of the .38 brass I reloaded was S&B, but I didn't record what headstamps had the seating problems. With my press, I do get the tactile feedback when seating primers, I can feel them seating. I usually just eyeball the primer depth, but I'll use a steel straightedge across the bottom of the case head now and then.
I do pick up a brass on the range when it's there, and I think I'll continue to sort by headstamp since I've been picking up .45 ACP brass with both large and small primers.
I've mostly used the decapper built into the resizing die after tumbling, and there has occasionally been some media buildup around the base of the press ram and in the slot where the primer seater pivots on the pin inside the ram, but for that, again I just use the compressed air to clear the stuff out of the press mechanism as needed.
I'm still undecided on tumbling before or after decapping. Each has its pros and cons - tumbling after decapping, I get more media in the flash holes but cleaner primer pockets; tumbling before decapping, I get more residue in the primer pockets. I've read that decapping before cleaning actually helps lubricate the die, but I use carbide dies that aren't supposed to need any lubrication.
As for chamfering, I haven't done that with any .45 brass yet, but I have checked case lengths with a dial caliper after resizing. Haven't seen any case stretching yet.