Got the Vivi's and modded both of them - they work!
It is definitely a tight fit in that tank, though. To remove the tank I use an old SS tube I have that is just barely smaller in dia than the tank. I put the tube in the top, invert the whole thing then push the plastic tank down. Came up with this after trying to remove the tank to clean for different flavor juice and had the center post come out.
I fixed the post with some loctite superglue and the pressed the two pieces back together. Luckily I did not break the wire when it separated.
My biggest problem right now is getting the ohms that I want. I only have #34 and #36 ga Kanthal and I either get too high (3.0+) or too low (2.0-) with only about three coils. I guess I will have to buy some #32 ga and then I will be able to add a coil or two to get the 2.2 - 2.4 ohms I desire. I would like to be able to use them on standard Ego batteries and not just my ProVari.
I coil them by first attaching the Kanthal to the negative screw - then I measure the resistance of the wire and crimp a piece of non-resistance wire to it. I then wrap the wick and, after putting two small washers on the center post, tighten the screw with the NR wire between the washers. This seems to work well, since you don't have to get the wick so close to the center post.
Since I've only been at it for a couple days, I think more tinkering will be needed to perfect the vape, although it is not too bad in flavor and vapor production right now.
I too am seriously thinking of a Z-Atty Pro, but for now the price is holding me up (no bullets!)

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