cross posted to rec.boats.cruising

Hi all,
Im looking at getting a cheap(ish) setup for my boat, i have a couple of
laptops with navigation software and charts, so what im looking at is a
couple of GPS units to hook up to them. Ive seen GPS receivers with serial
or USB connections that plug straight into a laptop, but these things cost
as much as or more than a basic hand held GPS. are they any better?

What im probably thinking is one basic handheld unit (maybe garmin GPS 72)
and one receiving antenna to plug straight in to the laptop. any ideas on
this setup?

Thanks,
Shaun