I think you may be referring to the KBQ (Karubecue) Smoker. If in fact this is the one you are talking about, they are beautifully designed, engineered and built of all stainless steel. They are not insulated. I read somewhere that this is by design in order for the draft fan system (+) to work as it's meant to. Bill Karau, engineer, owner, designer of karubecue could tell you for sure. I own a Karubecue and the downward opening of the door does not bother me in the least. Actually, it allows you to pull a rack out some without dripping juices or greases on the patio, ground, etc.
Like many others, I have owned and cooked on all types of smokers and grills, over the years - gas, charcoal, electric, pellet and now wood. The Karubecue is without doubt the best smoker I have ever owned or could expect to own. The inverted flame system design is genius. It gives you thin blue smoke without having to worry. The only thing you have to do it keep it fueled. Because it is a stick burner, it requires time and attention (as well as electricity) so it won't be for everyone.
I would recommend that you check out the kbq.us website thoroughly - including testimonials. Then read the reviews on Amazon.