I was told that it's good to mount it behind tint in order to protect it from UV rays. I believe I read it on there website somewhere. Seems to work just fine, and the upside is it doesn't fry on my dash board any longer. That thing used to get SMOKING hot during the summer.
Auto glass is treated to block UV but, even if it weren't, angularity of the windshield is perpendicularly parallel with the antenna lens. RD's need to be checked, factory recalibrated, and/or tuned before any UV damage would be apparent. My Bel RX65 is a 2004 model that been back to the factory twice over the years, and the last time was in March....speaker, antenna, upper plastics replaced, tune-up and firmware upgrade. Lens was undamaged but replaced with the antenna.
RD's are illegal in Virginia, Washington D.C., on all military bases and illegal nationwide in commercial vehicles. They're illegal in all Canadian provinces except Alberta, BC, and Saskatchewan. Note there's still some debate regarding Virginia....consensus seems to be that a licensed Amateur Radio Operator (HAM) can be ticketed but RD can't be confiscated.
Laser Jammers and Radar Jammers are illegal in the states of Nebraska, Minnesota, Utah, California, Oklahoma, Virginia, Colorado, Illinois and Washington DC.
On the subject of radar detector detectors, most of the newer models are full stealth to VG2, but only the latest and best can't be detected by Spectre. All of mine have VG2 stealth capability claims from the manufacturer, but show poor performance where auto-stealth is concerned. Upon the RDs alerting to VG2, it has to be immediately turned off or it will be detected. Makes no difference because I don't run where they're illegal.
Mounting recommendation for all radar detectors is level, straight ahead, and as high as possible on the clear part of the windshield. Radar is line of sight and the higher it's mounted, the farther it can "see" beyond the horizon....we're talking increased range in feet and every foot of detection's a plus. For best performance at capturing laser signals, it should be dash or lowest point windshield mounted; however, if you take a laser hit, it just means you've got a citation coming if you're excessively speeding.
The only chance you have against laser is a jammer and you're talking $2K plus installation for the very best front and rear countermeasures available.