I use a
Garmin 176 gps/chartplotter interfaaced with the lap top. I have been very happy with the set up!
Well during the trip I would bring it in and use it as an
anchor drag
alarm. At one point it hit the floor. Unfortunately the display quit working, although the
gps part still worked. So i just used the pc for plotting.
When we got back I called
Garmin. They informed me that the unit was 14 months old and out of warranty, bummer, but they would fix it free of charge. 4 days later it was back and fixed