Pit Minder or BBQ Guru

Has any one used the Pit Minder or BBQ Guru on the Bandara?
http://www.thebbqguru.com/

I first learned of these devices on the Virtual Weber forum where most of the posters own WSM and they are high on these devices. The guru that controls both chamber and meat would not be the one I would be interested in because with the Bandara we cook more than one piece of meat. I am going to give the Pit Minder a try on my WSM.

CaptFrank,
I tried a BBQ on my BWS. I too was taught to never close the exhaust but control the air intake instead. Hence, I didn't properly use the BBQ. With both air intakes closed and the exhaust open, it did increase my burn time by an hour or so. I returned the BBQ....$230 for an hour wasn't worth it to me. Since then, I have been playing with the exhaust. I can now bring the smoker up to temperature and close the exhaust and both air intake vents and get between 10 to 12 hour burn with only minor adjustments to the air intake without affecting the quality of the product. Maybe my smoker isn't as air tight as I thought that it was.
Mike

Seems strange to me that this "temperature controller" works best on eggs and wsm's, two pits that are known for reliable steady temps.

I use lump in my BWS, but I have read a posting where a guy with a BBQ Guru on his BWS gets 36 hours out of one fueling in his BWS.
Mike