I hope this turns out all right, I am uploading a picture I snapped of the Whistler Pro68, Pro78 and XTR695 side by side. I bought the Pro 68 as a present for my son this Christmas. I wanted to make some test runs compared to the Pro78.
Pro 68 slightly more sensitive on X band
Pro 68 about the same on K band.
Pro 68 4 to 5 seconds behind the Pro 78 at 60 mph on Ka band.
I not sure of the Ka frequency, I suspect 33.8 GHZ since I have encoutered it alot using the RX65 in tech mode. The road conditions typical for the Northwest this time of year, absolutely ducky (raining).
Notice that the suction cups for the XTR695 are much larger compared the Pro 68, this is one area that reflects the price difference. The radar bands can be turned off individually on the Pro68 which is a good feature to have. I would recommend the Pro 68 to anyone looking for an inexpensive detector that still gives adequate warning.