I have the T-962 and updated it with the United Engineering firmware here:
https://github.com/UnifiedEngineering/T-962-improvementsOnly other changes:
1) Added cold junction temperature sensor (DS18B20).
2) Replaced the masking tape with Kapton.
For the DS18B20 be sure to get one that meets the specification for working in parasitic mode.
I also used a standard TC (Fluke) calibrated against a mercury thermometer to adjust the settings for each TC in the oven. You can easily insert the extra TC through holes in the bottom so it is very near the oven's TC and calibrate each one separately.
Oven follows the profile nicely and works for a hobbyist like myself.
BTW, I got mine about this time last year. The prices on eBay were quite variable. I got an apparently new one (still in box with original looking packaging) from an individual in the US for about $100.