pgbnh wrote:
The installation of the GNS530 is complete. The learning is just begun. But
since I now have equipment which allows it, what is the likelihood of
receiving 'cleared as filed' if I file direct to a destination a few hundred
miles away?

In the northeast, not likely. But, what does seem to happen is you
get cleared on airways, and keep getting direct to a fix two waypoints
ahead, effectively cutting off most of the corners.