I used to have a Garmin GPSMAP60CSx and loved it. However, just not going to carry both to the woods again now that the technology of phone GPS is so good now.
I used my Droid X2 and Cabelas Recon app last season and left my GPS on for hours and hours just to see if it would kill my battery like I had read on the tech reviews. I do have the extended battery but I still only used about 10-20% of the battery on a all day hunt.
I guess if it were a true backwoods excursion with no juice for a week then yes, a Garmin with lithium batteries + spares would be a good thing. JMHO....