Just an update: Long term testing indicates 15-month drift to be ~6ppm, and 30-month drift about ~9ppm.
Contrary to what one might imagine, many of my buyers mention this thread and the collection of critics who refuse to even test the device. Apparently the criticism is practically inert. It generates indignation in others, which makes them more prone to purchase from me.
So, thanks for all the free publicity!
I’m one of the critics early on in this thread.
I tell you what. If you send me one I’ll do a fair assessment of it and put it through the paces on a calibrated meter for 30-days. I’ll even send it back if you’d like.
I’ll be completely neutral in the review I give. You’ve literally got nothing to lose.
I really appreciate the offer. But the testing you want to do has already been done many times, by myself and by others. We do recal the units, so we get a pretty good idea of long-term drift.
Any reviewer that wants to be taken seriously cannot allow the manufacturer to know the review is being done. For one thing, the manufacturer might send a hand-picked specimen. For another, unless the reviewer's reputation is valuable it's easy to bribe him. You have nothing to lose if I offered you $500 to fudge the report. But if I have no knowledge the review is being conducted, then it must be an honest review.
So, no offense. It just wouldn't be credible if I sent you a standard to test.