I had never used a GPS unit before, and have very recently bought a Garmin 196, and i´m very happy with it after taking it up on it´s first flight.
Very easy to use, very informative, big display screen (for a hand-held), an excelent piece to bring along on a cross country flight. Not too expensive (about 420 £ new, but with a lot of accessories thrown in on the deal, such as the yoke mount, power cable, PC cable, remote antena, etc...).