This is a great thread.
I'm looking at a 3-4 hour drive to pond-able land that I can afford (near NY City) and am thinking about it like Jeff. There is only so much satisfaction I can get out of my aquarium.
My wife (who said "stop talking about your pond and start doing it", bless her) still doesn't like long drives. Finding a 15-acre pond 5 hours away would NECESSITATE a close hospital ... because it would kill me to pass but I probably would.
For me, it comes down to a simple question: can you do the trip in a weekend?