I haven't used that one. BUT...I just set up a rack with Flex Watt; and using a Herpstat and love it!! I have been battling with the UTH on my tanks with a Repi Temp 500R for 3 months. The Herpstat keeps my temps at a steady temperature.
hey ethan, i was wondering this myself. i own a couple of these and they work great with an UTH, but now i am running out of room for more animals unless i build a rack. on the hydrofarm site it says that the thermostat can be used with multiple heat mats plugged into a power strip, so i would guess it could be done with a reasonable amount of flexx watt.