i have 5 offsets. A double lang 84, A klose backyard Chef, My Old Bandera, and an old Silver Smoker and a Huge Shirley..
the double langs and the backyard chef, once up to temps need a stick every 45 minutes to an hour, if your ok with larger swings in the heat, you can go to 2 sticks every 90-120 minutes, but you will spike the temps buy about 50-75 degrees. the cheaper offsets use smaller sticks., but need to be fed more often.. the big shirley gets fed every 75 minutes.
Temps in offsets are controlled more by fire size than draft.. Smaller cleaner burning fires with open draft is what i shoot for. Making the fires too big, and then dampering down causes the fires to choke out and you risk some bitter smoke..
with all this being said, I love the offsets.. you get to learn fire control, smoke control, pit characteristics, controlling draft, when to keep heat in, when to dump it, spike the pit to get thru a stall, then level out to finish.. cooking on and offset, on a summer day while your fiddling around in the yard is a therapy cook.. the smell of the wood, and the rub and the meats while your mowing the lawn or vacuming the pool is therapy... and it makes the neighbors drool.
An untuned horizontal offset will give you a versatile pit with heat zones across the length of the chamber. These zones, once understood, allow you to cook different meats at differnt temps. A reverse flow offset, or a tuned horizontal will give you a more even, left to right chamber temps. I always enjoyed the science involved, learning the pits characteristics, draft control, damper effects, etc.. .. etc.. and IMHO, there is nothing that can beat the depth of flavor imparted by an all wood cook.. Ive done many side by side comparisons with lots of guinea pigs(aka, friends and families) comparing the stick burners to the pellet cookers and the bullets and the stickburners won 100% of the time.
dont let them spook you.. yes there is a learnign curve, but thats what BBQ is all about.. its a craft.. learn the craft, have fun.. and reap the rewards by sitting at a table of awesome bbq, a few beers, family, friends and dirty napkins.