First of all, welcome to Lemmy!

When confronted to that decision, I ended up thinking that I'd want a tablet that had good image quality, and a screen close enough to that of a comic to be able to see a full page comfortably. When I looked (back in 2020), the tablet market was basically divided into 3: Amazon's Kindles, iPad and Samsung. Amazon's are pretty low-cost, which is enough to read comics, but the screen is quite low-quality, and reading comics on a screen instead of paper is already a step-down to appreciate the art. And I prefer to avoid Apple, which left me with Samsung as pretty much the only choice. The Tab A series don't have AMOLED, and the only advantage the Tab S6 had was to use a stylus (which I wouldn't have bought, or even used if there had been one sold with).

So I ended up buying a Galaxy Tab S5e. 10.5" is really great to be both light and portable while big enough to display a full comic page, and the super AMOLED screen is amazing. It's been going strong for 3 years now, and I've used it daily to browse the web, watch movies or series, and of course mainly to read comics. When that one gives up, I will look for a similar form factor, unless a good, large enough color e-ink tablet comes out by then, in which case that might be what I'll pick.

As for usage, I transfer everything through FTP and store the comics in the tablet's storage. Then I use Perfect Viewer to read them. It's old and hasn't been updated in a long time, but I haven't found any other reader as convenient. I've read that Tachiyomi is great to read comics and manga, but it requires a specific folder organization to read comics locally, and I'm not willing to give up mine to use a reader.