At the back, right hand side, there is an area where the element is not under the wood chip tray. This doesn't seem to be a problem if you're using the upper racks but on the bottom one I've had some scorching of the drippings at this corner on a tray I used above the water pan.
You may want to experiment a bit with a temperature probe at the different rack heights to get a feel for what the differences are as the built in probe on the back wall doesn't necessarily tell you what the temp is over the water pan.
I notice mine gets hotter on the right side. Probably because the element is on the bottom right and the exhaust vent is on the top right. Then they go and put the thermistor on the middle left. If I were designing it, I would have put the element on the bottom left, thermistor center back, and the exhaust on top right.
My built in probe is as accurate as my other 2 probes. I wish it had a alarm and I wish it was removeable. I end up using my old probes as they are easy to clean and will beep when done. I do like the window.