I've got a Vault, with the ball valve design, and a WiFi guru. Here's my thoughts:
1) If you go with a Vault, get the ball valve design - it's a must
2) If you go with a Vault, get a guru - not a must, but it's been really nice
3) If you plan on moving your Vault, have friends available - they say those casters can roll on anything, but it took me and 3 friends, and lots of plywood, to move it 150 feet into my backyard
4) If you decide to do business with Pitmaker, stock up on pain killers - doing business with them isn't that easy
At the end of the day, I love my Vault. I've got 4 smokers in my backyard, it's the only one I've lit a fire in over the last few months. But here are just a few of the issues I ran into:
1) Lengthy delays while waiting for a quote
2) Lenghty delays waiting for a call back to place the order
3) "There's no more extensions available for me to transfer you" when calling the receptionist asking to talk to Sales/Support
4) Pit was late being shipped
5) Was told shipping would be 1 day (Houston->Dallas), it took a week [Side note: not really their fault, but don't say 1 day....]
6) Was shipped the wrong adapters & guru that I paid for
7) Took about a month, many unanswered emails and phone calls, before the correct Guru & Adapters were shipped
Justin (J$) ended up helping me a ton during the process, they should give him some commission as he kept me from canceling/returning the Vault, and now I'm a happy owner.
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Regarding burn rate, I loaded up 6 pounds of lump this weekend to cook a brisket - here's my chart:
There's still some coals left in the basket - and you can see the Guru barely had to run once it got up to 225-250.