Have a UDS, looking to start competing in about a year and a half, planning on buying a Meadowcreek offset (SQ36) in the spring. BUT it sounds like WSM's are the way to go. How often do you have to add fuel to a WSM over a long cook for butts etc? my drum will run forever on one load of K and some apple wood.
If you load up the charcoal basket, you'll have charcoal left over to start your next cook with.