On my 2007 avalanche I could easily document the "highway miles". The odometer saved the miles AND the total engine hours (not resettable like the average MPG). So let's say I had 200,000 miles on it and 4000 engine hours. That means my average speed was 50mph. If my average speed is low then obviously it was more stop and go.
My favorite posts are 125 k on the motor, 75k on the transmission and the body has about 300k+.
buts it is highway miles so that makes it "better"