A little more info.
I started with about a quarter of a 12 lbs bag, used a chimney to get going. I didn't take notice of the exact time to get up to temp. Just was longer than with the briquets and the temp fluctuated for a good 1.5 hr or more. The vents were all wide open for most of the time. Now. after about 2 hrs or so I was real impressed with RO holding a good temp, but I did add a chimney full of briquets.
Pics, will be added, I smoked 2 meatloafs btw, and had about a third of the bowl filled with warm water, to start.
Again, thanks for the replies. I am not done with RO, I did like the way it held temp, just seemed like a long time, effort, couple hrs. to get there.