After waiting for the last few months on GPScity backorder list just to keep having the time pushed back, I saw my local REI (Reading,MA) had the 600 & 650 available in store. Ran right over and picked up the 600. Loving the 600 over my 450...loads super quick with very many maps (have OSM for NA, the 24k NE & West topos, North America City Nav, and some KMZ files) and well over 20,000 caches. Even got to use the new GSAK beta to try the new GGZ format and works amazingly well. Very impressed so far!