I've been using this since our local wally world stopped carrying R.O. I smoked a 9lb brisket and used around 1 1/2 bags on a 10 hours smoke. Although could of probably used less but was experimenting with a new baffle.
As for how it burns, i used a bag around 12 months back. Was awful stuff, popped and cracked and didn't last long. The bags i bought recently were a lot better. Had a god amount of large pieces, not too many small bits. I didn't notice any popping or spark showers, and it lasted a decent time too. I guess with lump it is possible to get a bad bag since it is not a uniformly manufactured thing.
My only reason for using the R.O over Kinsgford is the price. I get (was getting) R.O for 5.95 and the Kingsford for 6:99.