That's a nice set-up for your
AMNPS, and the rack sells for less than $8. I know some say that the water pan in place helps the heat distribution. I have smoked with and without it - both turned out fine, although I only used a couple of higher up shelves. I sent an email to
Masterbuilt asking that question about needing the water pan for heat distribution a month ago. They never answered, surprise, surprise! I would also agree that obviously the bottom shelf would be hotter than higher up.
Dennis