The Duracell looks like a really nice unit
but it's also a bit pricey relatively speaking. I got the unit pictured below for $20 from an Advanced Auto parts store (through Slickdeals.net) I think that is a clearance price. Then went to a local electronics store and got the 12 volt plug and the jack for less than $10. Unfortunately, I don't have any "action shots" but I have used it for cooks from start to finish and it worked like a dream.
Weber Summit S-670, Backyard Bomber MJH, Weber 22.5 WSM, Mini WSM