zimbop,
On vacations and the first three years of my 5-speed Insight I drove fast more than occasionally. It seems I'm failing to get the point across that if you want to cruise anywhere from 60-75mph, you can still save gas being one with the dashboard and still save time.
The 5-speed Insight saves fuel on the highway by going into
lean burn. You can assume it's on when the instant mpg is above 50mpg. On a level highway, you can drive as fast as about 65mph on lean burn. Lean burn will cut out quicker with loads like the A/C or hill climbing.
My work commute is about 30 minutes and can go about 90 minutes before the seat really bothers me. Given a choice between going 5-10mph faster and the cruise control, I'll go faster manually.
Fuel Economy You Might Expect on a 5-speed Insight With a Light Load
80mph+ = 40mpg
75mph = 55mpg
70mph = 60mpg
65mph = 65mpg
60mph = 75mpg (it's the lean burn)
While these are estimates, I hope this give you a good idea of what to expect
One other thing to add from a cost standpoint: when I routinely cruise at 75mph within a year I get pulled over in Texas.
lakedude, do you know a Vette is lower to the ground than an Insight?