Ive had my SXK for about week now. Ended up going back to my Cthulhu MTL yesterday though. The atty itself is pretty awesome, and the airflow wide open wasn't THAT much different so I kept it going for a week. The problem I did have with it is, it doesn't seem to like heavy VG juice. My DIY mix is 70/30 and it seems like the Prime cant keep up with it. I have the juice control open a full four turns, and you can see it wick and bubble when its first opened, but after a few vapes, it'll start to dry hit and you have to prime it to get it to wick again. Who knows could be my wicking though. I just did it like you would any other Kayfun. Just trimmed the tails so they hit the bottom of the wells, and spread em out so it was full. Still every 3 or 4 vapes, gotta prime it before it'll go again.. Build wise, mine seems fine. All the parts and threads go together nice and smoothly. JFC is fine, and less wobbly than the KF5 when its opened for thicker juice. AFC ring works great, I love the nice VISIBLE markers on it (I never even noticed the KF5 had them until a couple days ago). No bad o-rings or any trouble taking it apart/filling/building. Probably ordering a Zeus or Zeus Dual tomorrow though.