Shirley fabrication question

[soonerfan]

I have a deposit in at shirley fabrication for a 24 x 42 cabinet smoker. I am debating on either getting an insulated firebox or a three shelf warmer with a 1/4 or 3/8 firebox. Any suggestions from shirley owners?

 

[highlife4me]

I know this is an old post but your smoker probably isnt built yet because of the long wait list, I wouldn't get the insulated firebox, i would opt for the thicker fire box with the 3 shelf warmer.  The smaller cookers do not use much wood the way it is so there isn't that much of a benefit going to the insulated firebox.