I live in VA and use the Beltronic "custom installed" radar detector. This is a detector where you mount the antenna in your bumper (out of sight) and only have a small display inside the passenger compartment. It's almost completely impossible for police to see. It's also the most sensitive detector I've ever used. I'm sure this is because of the huge antenna mounted in the bumper. The antenna is about the size of a windshield mounted detector.

The below link is to Beltronic's "custom installed" detectors. I bought mine off Ebay for about $200. It's easy to install yourself (especially if you're used to doing mods yourself). I can include pix of mine if anyone is curious how it looks.

https://www.beltronics.com/store/custom-installed/