My new STi Driver is amazing on Ka band, but SUCKS on K band. I think I'm going to call Belscort and have them send me a new one. My 8500X50 and the 9500ix that I used, destroy the STi on K band detection. I know this can't be the norm, and it must be a defect. My job has a 4 K band door openers (double in and double outs), and before the other detectors would alert me while I was on the street perpendicular. The STi only alerts when I'm about to pull in the parking lot. When I left work today I went in front of it, beeped, turned left and it went quiet. I tried this on Highway mode today and it only alerted me to a Real K band threat when I was right on top of the police officer. Luckily I haven't sent the 9500ix back (60 day test drive ), so I can use that while I get a new STi.