Interesting... I will likely get one of these, though I'm still waiting for a high quality "lifetime" Vivi Nova style (screw-on head, leak-proof, with no need for an air hole in the top cap)
rba that is made out of surgical grade or space age (whatever) material. The VN is popular enough that I would think someone would want to do this and charge a few more dollars for it.
And OP, thanks for the build tutorial. I appreciate being able to read and look at how to do something without having to watch videos. Not that there's anything wrong with video tutorials, but they do not replace a written manual-style presentation for efficient learning IMHO.