Tank...Kanger T3S Clearomizer...
Mod...Vaporesso Target Mini...
..
I started and stayed with the "Tabac BCC" (later known as the T3 and upgraded to the T3S), once clearos became stable and went bottom coil - after abandoning the first top coil "Royal Smokers - E1 though E100 lol....hated the vivi novas

Kanger's T2 (earlier known as Tabac CC) top coil wasn't that bad.
While I still have some T3S's, I switched to the Eleaf GS Air M and recently got the Nautilus X with the 4ml extension, mentioned in a more recent post. I'm liking the Naut X, but the extension chimney comes off 50% of the time for the top refilling. Not a big deal but I'm thinking about tightening it more once I do a coil change
Even though the T3S and the GS Air M were "virtually" leak free, there were times when the eliquid level was low, where you'd get some leaking. With the Nautilus X top air control, there is simply no way for the clearo to leak at the bottom. I suppose it could leak at the top but so far that has not been the case, whether it's straight up on sideways in a pocket.
Another thing I want to mention is that with the Kanger kbox Mini-C, it was stated that the colors were infused and there were a few posts about the black one which was also considered infused - it isn't. I'm getting some scratches on it. The 'space gray' - actually better looking, imo, than the black, and the silver show no scratches of 'discoloring'. Just FYI to those following those older posts on that.

I have no info on the white or copper mods - suspect the copper is also infused but likely not the white.
For an internal batt mod - the Eleaf iStick TC40W has been great. That and a GS Air M would be a very good starting 'kit' for beginners, or for people who think they will exist past all the deeming stuff, and aren't into 18650 mods. I've stayed with the mini-C for those - as I've said before, they fit my hand and fist hold perfectly, as does the TC40W.