I think in my mind I had inadvertently munged the prototype QQ you have with the heaters in the final release. Meaning I thought Matt had actually gone the route this time of a coil inside the alumina tube. You are of course absolutely right, now that I look at the picture of the tubes again they have an embedded wire and solder just like the donuts. The OF post is super informative (the bit at the end always makes me laugh) and I thought Matt did have the v3 donuts tested for off gasing but can't find the post to the report? @divinetribe? I do think as you said these are concerns rooted in suspicions but not actual data. However, I also understand the fear even if unwarranted. The attitude many people seem to adopt is "avoid unnecessary materials at all cost". This reductionist design philosophy for vapes isn't a bad one but I do think there is a a literal cost that comes with it. For example, an alternative could have been to leave the SS wire leads poking out after embedding the coil into the alumina. Then the non resistance wire could have been attached to the SS via a gold crimp. That is more expensive materials though and I imagine would add substantially to the assembly and QC costs (not to mention introducing another point of potential failure). Tradeoffs as always of course! Personally not going to fret much as long as the solder is actually silver and appears properly sealed/coated as OF describes. As always, it would be awesome to see a materials report and results of off gasing test. Probably the easiest way to alleviate any customer fears (even if unfounded).