I use a Garmin eTrex H. Never had an issue, and its the only GPS we have between myself and three kids. I spent 99.9% of my time on the 'goto' screen: very simple screen with nothing but an arrow on it to show the direction of the cache, the distance to / from the cache in miles then in feet, and an average of your speed with an estimate of when you'll arrive.
It's cheap, simple, and has WAAS. What more could you ask for?