Greatest invention in the 21st century (so far anyway)! Simple enough even old guys like me can use it without getting out the manual every time.
My wife bought me one before early grouse season last fall. Used it during early season, deer season, and late grouse season. Great for exploring new areas, and old familiar ones for that matter.
Will always carry at least one compass because I figure being electronic it will at some point fail. However, it seems to be real easy on batteries - I used mine for 4 months of hunting season and still has the original batteries in it.
One thing I noticed was that it seems to be much more accurate when you calibrate it EACH TIME you use it if it's been off for a while, and especially before you mark your truck's location when first starting out. It does take a minute or two to do the calibration routine, but it's worth it.