With drop-in coils: Nautilus Mini, Vika Fantasy clone (uses nautilus coils), eGo One tanks (with rebuildable CLR coils), Wismec Amor (can use the CLR coils)
I just got the eGo ones and the Amor, and these are now definitely my faves for drop-in coils. Great flavor, non-leaking, rebuildable = winning!
RTAs: Kayfun Mini 3 clones, Goblin Mini, Spheroid, Doggystyle clone (with a Digiflavor Siren on the way, as well as an Erlkonigin Nano clone coming, with the help of a kind ECF friend). I have some others that I don't use much, so won't list here.
Currently KFM 3 still my fave. The Goblins are good for flavor and easy to build, but have annoying quirks (V1: bottom fill screw; V3: Leaky McLeakerson). The Doggystyle is perfect except for the plastic tank.