GPS and electronic charts?
Electronic Charts are great. Garmin best!
Ozie explorer pretty good! Both are different
formats. Raster and Vector. Ozie cost $75 off
the net and sharewhare avail for 30 days free. It''s really quite good. However out of the US I''ve found 3 times the electronic charts to be off as much as 1/2 mile( putting you on land ). That is less than 1000 % of the time.