I just purchased a "like-new" AE4000U. I really love this unit except for one issue. My lower left-hand corner of the projected image is angled upwards. It's not horribly bad, but certainly is noticeable. I had a Panny AE900U prior to mounting this unit, and it never had such an issue - in fact, it never had an issue! I just wanted to go from a 720P to 1980P. Honestly, there isn't that much difference. I must have had a great 720P unit!
Anyway, I was just wondering if anyone out there has had this experience. My installers told me that my wall was not perfectly flat and since my screen box hangs from the ceiling/wall, "it's off" and this causes my image to be sent upwards in the lower left corner....but, again, I never had this with my AE900U.