I remember reading about the PBC (Pit Barrel Cooker) and I think they said they played around with different sizes and settled on the 30-gallon version because it offered better consistent results, but they couldn't explain why. Dr. Greg Blonder postulated that it had to do with the size and shape of the convection currents inside the 30-gal keeping more consistent temps and circulating smoke more evenly as well, better than either the 50-gallon or those smaller than 30-gal.
I'd have to go back and read more to make sure I'm remembering right. I just like the pellet burners due to the set-and-forget convenience. Using something like the A-Maz-N tube for extra smoke is an option, as well, since pellet burners don't impart quite as much smoke flavor as stick-burners. I've already got a set of the grill grates. Expensive, but they do a nice job when searing steaks.
I'd have to go back and read more to make sure I'm remembering right. I just like the pellet burners due to the set-and-forget convenience. Using something like the A-Maz-N tube for extra smoke is an option, as well, since pellet burners don't impart quite as much smoke flavor as stick-burners. I've already got a set of the grill grates. Expensive, but they do a nice job when searing steaks.