Riva 510. I've been using Vortex cartos for a few weeks and really love the no-fuss all-day fill. Having some
ejuice issues - I'm VG only, though I've been trying some 80% VG and it's mostly OK. Also, see the "so disappointed" thread in this forum - I seem to have odd taste buds. I have found LF VG Cola and VaporBomb Hypnotic Mist keep me pretty happy, but I'm still blowing my cigarette savings on sample packs, looking for my
vaping Nirvana. But I'm happy enough to only rarely think about the emergency cigarette in my drawer. It's probably all dried out, anyway.