Here is the original sales video which shows some of the capabilities of the Navion. Keep in mind few Navions have their original 185-225hp engines and many are 260-310 now.

"Action" starts at 4min:

https://www.youtube.com/watch?v=POEql5ALJjg

There was a time when off airport was a way of life, not a sport. There are still a few counties where the controlling authoritys allow spray operations off county roads. Big, fast, jet spray planes have mitigated the desire if not the need considerably.