I have no doubt that the larger size would be more beneficial for the bees, more enticing!! But its not more enticing to this old guy! Did you REALIZE that by the time I get a quarter mile from the truck my little swarm boxes weigh in at close to three hundred pounds??? Seriously!!! I think they absorb moisture or something!
To be honest, I have often wondered what I was missing by using this size box.. but at the same time, I have to think that if I were to catch MORE swarms I'd have difficulty hiving them. Farmers like their beehives, they just dont have time to keep them from swarming!