I noticed you came from a somewhat dufunct forum... Did you ever start you 500 gallon build ??? If not, use my tutorial.. It will guide you through a build to a smoker that works very well....
Members here used Feldon'a about 5 years ago... during operation of said smokers, some inherent design characteristics were noted... Thanks to the many members that put up with "speculative" modifications, until "we", as a team build, worked those bugs out...
There are members here that use their RF smokers to smoke cheese for hours at or below 80 deg.F...
Anywho, thanks for stopping in... We always appreciate good help.... Dave