I was asking myself the same exact question the past few days... still haven't decided yet. I have 2 KFL+ clones, one from Tobeco and other from HCigar, both have been working very well for me since I got them and I love them. I've been itching to get a third one however the Nautilus mini has definitely sparked my interest as well with all the rave reviews. HOWEVER.... the only thing that deters me from the mini is of course, having to buy new coils in the future. I'm sure these coils last a while and perform great but if you're bored of your coil in the Kayfun or need to rewick, its not a big deal and won't cost much to do it. A part of me has been enjoying making new coils as well. But at the same time, the plug and play with the BVC coils is nice too for when you just wanna grab something real quick. I know some people have been saying the BVCs vape better than the Kayfun. I guess for me, I'm just wondering if its worth it in the long run. I'm leaning more towards another Kayfun but... I'm gonna hold off for now.