I have received feedback on the mounting of my antenna behind my front bumper cover, and some of the comments were that the bumper cover would diminish the reception and effect off-axis performance.
So far, I have been extremely pleased with how my RD works with the antenna mounted behind the bumper cover, and last night I had an interesting alert. Reference the following picture:
I was travelling south on the freeway, exited via the off ramp onto McKenzie Lake Blvd and then turned left (eastward) onto McKenzie Towne Blvd.
As soon as I made the curve, I started getting a 34.7 alert. This road "arcs" where it goes over the freeway and you can't see what's on the other side, so I thought perhaps the cops had a speed trap set up further down the road.
As it turned out they didn't, but just past the traffic circle I noticed a big "Checkstop" bus that the local cops use when conducting checkstops (looking for drunk drivers). The bus was located where the blue line is. Parked on the opposite side of the bus was a police cruiser with the 34.7 Ka in C/O (the smaller yellow line). I've drawn a couple yellow lines to show how he was facing / where his radar was aimed.
The map says the distance from where I got the first alert to where the cruiser was parked was .6 miles. To me, this was pretty good, as the radar was basically at 90 degrees to me, about half a mile away, and my unit still picked it up.
So if my bumper is affecting the performance of my unit, it can't be by much.
It was in highway mode, running segs 2,4,5 and 8, POP off, TSR off, RDR off.