PSA is currently having them for $350. I know the 5 series have had issues in the past but are the newer ones "fixed". Recently picked up a XPS2-0 and it's missing the thumb screw. Yep, just my luck. I have not had the chance to shoot it yet. Second optic if I don't go with this one is the Trijicon MRO. Optics planet had them for $420 plus 11% off (expired?) a few days ago.