This is what I ended up buying.
Rite Hete:
I have the pint model that I purchased on Ebay for $75.00
I ordered the quart model with the upgraded thermostat direct from Rite Hete for $479.00 plus shipping.
Really pricey units, but will never scorch the plastisol and the color stays consistent throughout the entire session no matter
how long you use it. You can even leave the unused portion in the pot to cool and reheat it again days later without any trouble.
I struggled with the initial cost, but if I had to do it over, I would have done it sooner. I love them.