I use my Sonocaddie all the time - and feel lost without it. It tracks your game and measures your shots too so soon you can hit it really close! I've improved my handicap by 5 shots in 6 months. As said earlier the range finder needs clear kine of sight. My GPS is great even when on the wrong...
Yep its ridiculous how some players do not. A club manager here in South Africa was telling me he was out on the course on a sponsored day when he saw a visitor leave a pitch mark so as they came off the green he spoke to the man asking to please repair his pitch mark. The guy refused saying!"...