Maybe I should give them a call. If I can get my heat shields replaced with the new one piece shield, it is worth a try. I've been fighting uneven temps since I've updated to version 5.6 and higher. It still cooks good, I just have to work with the different zones, which is to be expected; the JB is long and the firepot is not centered. You may still find some different zones, that that is kind of expected; as long as the variance is not too huge. I've finally got it so the far left is about -10°F than the center, and the far right is about +15°F, by adjusting my shields.
Do you have the three piece or one piece heat shield? If you have the three piece, they are probably sending you the one piece shield. What version are you running? I just updated to 6.2, but haven't had a chance to do a test run. I would be interested to know if the new shield makes a difference.