I've had mine located slightly below the top center of the windshield for about a year and haven't had a problem.
I wasn't aware of any recommendation by EZ Pass to place it at the lower center windshield location. Thanks tiffy2000!
2012 Newmar Bay Star 3302
Blue Ox Avail
BrakeBuddy Advantage
2015 Malibu
"Get busy living, or get busy dying."
Andy Dufresne, The Shawshank Redemption