While I use the belt sander for shaping limbs it seems that with the drum I can do more jobs.
Tapering risers for glue up,rough shape tips for final sanding,feather accent strips,rough shaping handles.I even have a drum set up with a bearing on the bottom that follows patterns for repetitive work that is awesome.I know I could do most of this with a belt BUT the level of pecision I get with the drum plus the ease of dust collection makes the drum sander a very important part of my shop.
I like how everyone has an opinion and we are all correct, I made do with just a belt sander for years,for me speed and quality picked up when I started using a drum in addition to the belt.
What part of Idaho are you from?