Guru PROCOM 4 for sale. This was used on my Meadow Creek 250 stick burner. The list price is between $600 and $700, but with some upgrades, I'm closer to a grand.
One 25 cfm fan was not enough to control the temp reliably. I added a second fan and a larger power supply for the added load.
This unit operates on 120 vac. However, I made a cable assembly to allow operation from a battery for when AC power is not available.
The unit has 4 temp probes which is very nice. I could monitor different areas of the cook chamber and still be able to monitor the warming chamber as well.
Holding a wood fire steady is a challenge, but this unit (with dual fans) did a great job which allowed the head cook to get some sleep.
Price $475, plus shipping
Call me at 610 698 9937