Jeff is a great guy. I met him when I went to pick up my Superior. He runs the machine shop where the Superior, Assassin, Rebel, and DW Kountry Kookers are made. He is hired by the guys who came up with the Superior, Rebel, and DW's to build their brand of smokers, and he has made his own model with what he thinks is the best setup for the Assassin.
My Superior also came with the 4" casters, and I didn't have any problem getting it to stop where I wanted it to or towing it without brakes, as long as you have it strapped well.
When looking at the Assassin, I like that it has the Guru hookup on the side of the firebox, and out of the way of the door, and the fact that it comes WITH a guru, so you are really only paying $2000 for the smoker itself, which is built like a tank.