Hi HKJ, thank you for sharing with us about your testing reports.
A saying goes that although Samsung 25R is the upgraded of 20R, 20R performs better than 25R. Is it true?
Well, trying not to be excessively picky, those TrustFire IMR14500s work well in fact.
I have a pair which I've just homemade freehand internal resistance tested, though I can't guarantee these figures to be 100% reliable because of the finicky seating of these tinies on my charger: 82 & 80mΩ. My bet is they can handle 5A continuous very well thus.
It's wide flat-top protrudes a smidgeon, so they can be set in series without problems.
I haven't tested that myself. They are reported to achieve a slightly lower capacity figure (≈10%) than claimed. It seems you won't find a much better product than this one in this category.
For a while now the EFEST IMR and WindyFire IMR are generally considered the best performing 14500 cells around, maybe slight advantage to the WindyFire's, plus cheap for flat or button top at $3 each. Richard at MtnE sells both, not sure where to buy overseas.
I think I made the request for the LiitoKala 26650-50As some time ago. HKJ said they weren't on his list…
Besides Mooch at the E-Cigarette Forum, I don't know of any other willing and/or capable of doing a decent review of 'em. My bet is, unless HKJ changes his review policy (which may be mediated), Mooch is our only chance for now.