Dug,
I took that shot on my way to Moab(Horace you putz
).
I did get it up to 170 on a nice straight away.
I'm not sure if vehicles here get governed. I'll tell you though, it was a stable ride and it was tempting to take it up all the way. But I was too chicken.
Being in a vehicle that size, it doesn't feel like you're going that fast.
I don't remember ANYONE passing me during the 22 hr flight.