I was just thinking of the working height. My 55 gal drum is around 39" tall and I have it on a barrel dolly which adds another 3 or 4". I am 6'2", and I would not want that section any higher. You have to decide what is best for yourself. I would just keep in mind what height you will need to load it at and also getting the "lid" section on and off.
Just some things to think about.
Charbroil Vertical Propane Smoker, Weber Silver Gasser, UDS, Maverick 732. Weber 18.5" Silver, Weber Redhead Stainless Performer, Blue Weber 22.5 Gold, 18.5" WSM