While vacationing in Fenwick Island, DE last week, I picked up a FI LEO running Ka; my range was about a mile...LEO was facing south, hitting north bound traffic just before leaving the town limits (35 mph in town, 50 mph just across the line). LEO was in a marked patrol car, minus the light bar on the roof, parked in a hotel parking lot (very tricky to find!).
Needless to say, he collected a lot of revenue!
The other encounter I had was entering Rehoboth, DE. Town LEO was facing north bound just past Silver Lake; LEO had rear Ka radar and was smart enough to sit near the portable "Your Speed" sign. LEO was using I/O, I only got about a 300 yard warning, but it was enough for me to pull over and allow the tailgater behind me to pass (I guess the tailgater didn't have a detector)
I did get the K signal before the Ka registered, but since the K was constant, no big deal.