That SXK DoggyStyle 2K16 looks interesting. I'm not thrilled with the bottom fill style, but that isn't necessarily a deal killer in a 3.5ml tank, especially at $10 a pop for one of these. It's cheap enough for me to buy one or two to try out anyway.
With my 22mm Siren I've been using a 3.5mm ID coil, which I wasn't putting enough wick in, so I've dry burned the SS316L coil and stuffed it with more wick, going all the way down to the base of the tank this time with the tail. My first fill of one of these tanks after replacing and priming the wick usually doesn't seep very badly, if at all. My first fill with this setup was no different. The follow up refills will show me if I've improved anything or not. As always, I will report back my results.