Anyone interested a DG I have a one out of a pa28/6 was going to put it into my bird but went with a hardwired avmap iv instead asking $225 for the DG. Liked the idea of the avmap showing all of the restricted airspace. I fly to close to Washington DC to screw up. The problem with electronic nav aids is they can die without notice thats why I have a backup Lowerance airmap 500 as a semi permantent installation . I operate a charter fishing boat and often operate 50 to 60 miles out to sea (all ocean water looks alike)and would never just relie on one GPS to navagate. Time speed and distance using a compuss and clock(dead reckining) never fails. While at sea I plot my position every half hour. There is not one question on the Coast Guard Captains license test about electronic navagation. Professional mariners need to understand set and drift same as aviation wind triangle navagation.
To be honest GPS has made us into a bunch of lazy navagators. When I learned to fly 40 years ago it was about looking out the window still not a bad idea unless your IFR Len
