I just drove from Central California to the Texas-Louisiana border. I did the 1900 mile drive in three days. I had my handheld GMRS radio on and scanning for the whole trip. I heard one person talking on a repeater west of Phoenix, AZ. Somewhere in New Mexico I heard a couple of people talking car to car. I was stuck on I-10 in Houston for three hours due to an accident four miles in front of me and heard nothing. I also had a 2m/70cm handheld on, scanning, and heard very little traffic. Both radios, KG-905G, and Yaesu VX-6R, work perfectly. Interestingly enough, when I reached my destination I found a juvenile detention facility using GMRS radios. The facility is several miles from where I am.
I was surprised I didn't hear more traffic on either the GMRS or the HAM bands. I will reverse the trip next week and will keep the radios scanning.
As an aside, the 3200 mHa battery in the KG-905G lasted the whole trip scanning 12 hours a day for three days and is still showing over 8 volts.