About paying extra for a detailed calibration certificate I can understand that if that means the sales price is lower without.
The only reason why I would like it is for a peace of mind that it was properly calibrated, I just check the spec sheet and the last calibration date in the device.
Many are not only buying a measuring device but also a measure reference with this one purchase.
So the sheet included that says it's calibrated is a bit pointless to me, I mean what do you expect, a sheet that says the device that you just bought does NOT comply with the PDF specs?
Maybe Tek can provide some key factory calibration numbers on their website via your account after registration. (Would be strange if they do not log the calibration data in some database somewhere)
But like I said, for me it's just a peace of mind thing that the device didn't slip through calibration, I have easy access to 4 6.5digit DMM (3 different brands) with one yearly calibrated, so I can more or less make my own peace of mind about its accuracy.
And about criticism for Tek via E-Design I'm sure he can take it and that's also part why he is here to know what we think about it, to improve if possible. uh-hum
Personally I still buy the same DMM6500 again despite its flaws, it makes a nice bridge between DMM and Oscilloscope, almost all my (IoT) measurements I do with the DMM6500 only.
Some flaws are a bit like: you see the perfect smartphone but they only release it in a crap colour and then you start complaining about their colour choice.
So if people complain about it it's because they like to use the device, if they stop complaining it's because they moved on to another device. So E-Design, I'm sure you don't want us to stop complaining