Informative. #1 in Product Support for 2009, the Carlson Surveyor+ loaded with Carlson Software's SurvCE is a powerful, rugged and flexible solution for surveying & GIS. Carlson's leadership as the #1 selling handheld data collector in 2009 continues. Introducing the Surveyor+GPS with integrated GPS+GLONASS, L1/L2 RTK technology. All existing Surveyor+ units can be USER UPGRADED to the Surveyor+GPS. Accuracy is 1cm or less with RTK correction and .6m WAAS correction only, Applications from survey grade to recon to GIS, Carlson's Surveyor+GPS is a great tool.