I was looking to see if there were any video's of a Lowrance HD-8 series of the unit in chartplotter mode but i couldn't find one. Lowrance makes great. ( fishfinders ). sounders but how do they compare with the Garmin GPSMap chartplotters. Was thinking on buying either a Lowrance HD-8 or a Garmin 4008 or 4208., any opinions on which would be the better chartplotter. Tug