I bought one of these bushnell speedster guns to clock my sons rc cars. This is a K band gun it has a range of about 1100 ft on full size cars, and rc cars out to about 200 ft. I tested this gun with my escort 4600, I had my son shoot my at about 300yds. we had 2 way radios as I turned the corner at 300yds. I Instructed him to shoot, I got hit with a full warning of K band and he got a reading of 15mph. Another test I performed was a quick trigger from in the car and the escort 4600 never alerted. I will try this test with the new Pro 78se with pop on and off just to see what happens. When I tested this gun on the highway standing on the side near a strip mall I was able to get readings on cars as far as I could see them. The readings popped up instantly. One fast trigger pull instant reading I can't believe how fast this gun is, and the range is unbelievable for an $80.00 gun. This gun also scans and locks in the highest speed when the trigger is held. I even clocked a dart being thrown at a dart board 21 mph LOL.