I've never had issues taking 1.5 hours to do a proper test on a disc using a Plextor PX-712a or PX-716a (using PXScan), along with my regular BenQ and LiteON scanning.... but testing Dual Layer media, and having those tests run for 3 hours per disc (still plus BenQ and LiteON testing time) is driving me a bit batty!
Stupid double capacity taking twice as much testing time!