 Re: I75-I40-I26,
If you're going through Knoxville on a weekday, watch out for unmarked units (saw a blue Crown Vic and a black Charger last time) on I-40, I-640, and I-75. I am pretty certain that Knoxville also has officers on motorcycles.
I-40 between Knoxville and I-26 can suck at times. I saw numerous NCHP units (slicktop Charger, slicktop Tahoe, Crown Vic, etc) either in the median turn-arounds or hidden in the grass near some on-ramps. I have no idea what they were running. If I had to guess though based on how they were parked, I would say laser.
I-26 around Asheville was not bad the last several times I went through. I think there may have been one NCHP unit parked in a turn around, but other than that nothing.
SCHP has gotten sneaky with their new Crown Vics. The light bars are clear (LED), and the cars (which are a silvery color) no longer have any markings on the back. So! If you are coming up on one from behind, it is at times very difficult to tell until getting up close. SCHP also does have some slicktop Tahoes, but I have not seen too many of them around. Unless you are traveling during a holiday period or special enforcement time, I don't think you will have to worry about many unmarked SCHP units. | 
