Which is best for cleaning the inside and primer pocket?
Tumbler with media (what I've been using)? Ultrasonic? or Thumler's rotary tumbler with stainless steel pins?

The ultrasonic may clean out primer pockets I don't no. I use a primer pocket brush. Good luck.

Vibratory tumbler with treated corn cob media. Primer pockets I clean individually by hand after depriming with the simple little tool made by Lyman for that purpose.

Thumbler vibrator . Don't like the rotary at all.Walnut shell rules.

For that, wet tumbling is the best. But I prefer dry tumbling with corn cob and polish.

I do the same thing. Cleaning the primer pockets by hand only takes a few minutes and while I'm doing it I give each case a quick inspection. Helps weed out the bad cases. Been doing it so long I don't think I'll ever change. When something works, stick with it.

Does tumbler/media do a good job on the inside of the case as well?

Yep. The stuff gets inside and cleans it up really nice. I put the tumbler in the garage, toss the brass in, turn it on and forget about it for 24 hrs. Comes out looking brand new. Then I take the brass out, dump the media out of them, use a paperclip if clear the flash hole, give it a quick visual inspection, put it in a reloading block and give it a quick blow with the air compressor to clean the dust off. Ready to load!

Vibratory cleaner, corn cob or walnut, dry, primer pocket brush and inspect each case while cleaning the pocket.

See, I disagree. I use corn cob media and the primer pocket and the insides do not clean up. That's what I'm trying to determine with using the steel pins method.

I take it some of you much prefer the walnut to the corn cob?