Not sure why you hold off on the build. The kfl+ in stock form is outstanding. Build it as is and enjoy, then tweak. I own a few nano kits, and find that they hold too little juice. And the avid kit I looked at is not only too small, but looks like a leaker. You will find out soon enough.
If you want a shorter topper, look at the short tanks from SvoeMesto. I like them well enough. If you vape tank crackers, get a glass kit from science of
vaping. The top cap threads onto the chimney, holding the Pyrex (not Quartz) tank in place. Works very well, does not leak, and is fairly durable.
I also find that the shorter chimney on a nano kit vapers too hot for me. One of my setups right now is a pico kit from mod factory via cloud9. I fit it with a Pyrex wider bore tip from spectrum tanks. Nice setup on an 18350 mod. Very pocketable and a nice vape. I will try to post a picture tomorrow.
In anticipation of you getting your KFL in service, welcome to the club.
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