I can't speak for Dave, but I do use an AMNPS and an AMNTS in my #3.
I only use it for cold smoking cheese and bacon as that is the only time that I really need extended smoke.
Meat only absorbs smoke until if reaches approximately 140° and continuous smoke applied after 140° can actually add a bitter taste to the meat.
Depending on the smoke and how much wood that I use, I can regularly get a lot longer than 2 hours of smoke. I am guessing that I usually get closer to 3-4 hours of smoke on my of my smokes which is more than plenty.
To me the A-MAZE-N products have their place for cold smoking, but for anything else they are not necessary and just add extra work to my smoking process which goes against the Lazy-Q process that I so covet.
So, this is my 2¢