Thanks for the input everyone! I just wanted to make sure 11 inch wasn't overkill for such a relatively small space. As for the t-stat, no worries there, going to run it off a Herpstat Pro.
Thanks for the picture Shrap! I was a little worried about the sort of 'bump' in the back of the cooler, but I see your's has it too and the flexwatt appeared to be staying down fine. I am super thrilled about the see through doors, we were looking for cheap wine coolers FOREVER and finally found two identical ones for cheap. They were a little dusty/dirty, but they cleaned up nice!
Now to order the heat tape and assemble everything. I plan to install some suction cups or something of the like to hold an accurite or two up against the door. Also, does cutting a small hole in the insulation of the door sound fine for running heat tape cord out and probe cord in? Sounds much easier to me than drilling holes.