I bought mine from Canvape - they have the Tobeco clone of the Kayfun V4 for $25. Already got it, tried it, it's not bad, well made, very solid, all the parts screw together nicely, though I did give it a full sudsy bath in boiling water before use since it seemed a bit... I dunno, not oily, but slippery.
I dunno if the Kayfun V4 (clone) is the
tank for me though. It runs through a TON of
juice, and to be honest, it isn't tasting any better than the Atlantis or the Kanger subtank Mini. If anything, the Subtank mini is better, and you can build coils on it.
Another side note - the gaps between the mounting screws on my Kayfun V4 Tobeco clone are a bit off - on one side, they're very tight, on the other, better spaced. Makes it harder to avoid shorts when building a dual coil setup.
- M