When using my d.o. I use the lid and bottom coals method. The Volcano is a favorite with some cast iron chefs but when I saw one demo-ed, I realized it didn't fit my style of dutch ovening.
My lighter weight/small d.o fits nicely on my Cobb grill. The Cobb is my favorite because you can roast a chicken with only 8-10 briquettes as well as grill items without flare-ups. It's light weight, portable and handy for my style of outdoor cooking. It has gained in popularity around the cast iron chefs but again, it depends on what you cook and how you like to function in your outdoor kitchen.
Here's more info on the Cobb if you're interested in comparing the two.
http://www.cobbamerica.com/