I use resistance heating on uninsulated stainless steel fermenters of similar volume with PID temperature controllers, thermowells and Pt100 sensors. They maintain a temperature within ±0.2ºF of the set point.
But for the sake of argument let's say you are correct and 1 degree is pretty tough...
True! There is a change the manufacturer could implement to remedy the heat loss issue. If there was a thermal break where the interior and exterior stainless steel meet at the top the internal heat would be retained and not conducted and dispersed to the exterior shell.
That 2 degree loss in 60 minutes was when using the optional ($79.95) MTSs Temperature Control which has a 12V adhesive heater pad and digital temp controller.
http://www.ssbrewtech.com/products/mtss-temp-control-for-infussion-mash-tun
"You simply set your target temperature and the heater...
Caveat Emptor - Even with an extended pre-heat and using the optional MTSs Temperature Control my Ss Infusion Mash Tun loses 2° F in 60 minutes. The optional MTSs Temperature Control is grossly under powered and at best only slows the heat loss.
The mash tun is double wall stainless steel...
The Amana AZC31T15D and Whirlpool WZC3115D exterior dimensions are the same.
http://www.whirlpool.com/digitalassets/WZC3115DW/Dimension%20Guide_EN.pdf
http://amana.com/assets//amana/pdfs//DIMENSIONGUIDE/AZC31T15DW_Dimension%20Guide_EN.pdf?PIPELINE_SESSION_ID=4bdbbdc217144f8cbe1491413b637d00
The purge time depends on your regulator's setting (for mine ¼ - 8 liters per minute) and the volume of the headspace of your container. In the video the headspace of the aging sour was less than 250ml making the purge time brief.
When purging and doing pressurized transfers I prefer using a...
For that I use a stainless wand connected to a CO2 tank regulator via a gas ball lock disconnect. I insert the wand through the airlock to purge the headspace of a carboy, bucket or keg with CO2.
CO2 Purge Wand - YouTube
The purge rate is selectable from 0-8 LPM. The regulator attachment...
I modified a large syringe to allow me to pull samples of my sour beers from carboys and kegs with minimal oxygen introduction and only slight disturbance of the pellicle.
Sampling Syringe Video - YouTube
It requires a 3½ ounce (100ml) syringe with a ¼ OD tip, a small piece of ¼ ID...
A cold-pressed bottled coffee steeped in stainless steel wine tanks, free from oxygen, pressed and filtered twice, flash pasteurized and bottled with a drop of liquid nitrogen...
http://youtu.be/AgQyIAPy9i8
Pure Black - 2 Pack...