I don't know exactly how many nm the tour covered for me as I have US Roads installed and tried to follow it as accurately as possible. Mostly the provided flight plans were accurate with the highway in sight and only of place where both USR and FS scenery were both missing the road.
It was great to see scenery I mostly fly over at 33000 feet. I was surprised that even the default scenery has a reasonable level of terrain data and some towns look quite realistic.
I also enjoyed flying a biplane, I'd never really tried it before and the slow crusing was not as boring as I feared, I've never hand flown such a distance and time, so I hope my skill level has improved.
Give it a try, it's worth the time and you get quite a hefty virtual paycheque at the end of it.
