During the burnin process I thought I'd check the stone temp with my IR gun and found that it only reached 660 F when it was set at 800 F even after 50 minutes. So thought I'd characterize the stone temp across the range of temperature settings. The attached plot shows the average final stone temp versus the set temp. The final temp is always lower and gets to be a larger error the higher the temp setting. The final 800F temp reaches around 660 F or a 140 F lower than the set temp. I've submitted a support request so I'll see what they say.