I am duly amazed!! I've been using differentially corrected GPS systems since 1996. Sub-meter units were @ $2500. For reliable units the going rate is over $1000. Then the sub-meter subscription annual cost was on top of that. Then WAAS came along. Then RTK (Real-Time Kinematic) came along with a big price jump but with sub centimeter accuracy. Google Earth's resolution isn't sufficient for LR tuning. I have no doubt about that. BUT......I used a bit over $100 bluetooth gps unit tucked under my cap, an iPod with Motion X software to layout my back yard range. I cleared some sage, did some leg work, chopped a few Russian Olive trees and marked waypoints at the shooting spot, 500, 700, 800 900, 1002 and 1167 yards. The distances to the last two target spots were determined by sage brush and backstop locations. I entered the furthest two distances into the GIS (Geographic Information System) in this case, Mapinfo. Then measured the distances from the shooting spot to the waypoint locations. The results were as stated above, 1002 and 1167 yards. My thinking was that they were within maybe 20-30 yards of the calcs. Low and behold we put a PLRF 10. My mind was totally blown!!! The PLRF 10 was accurate enough (small, crisp beam), using a monopod, to select the intended sage bush, and came back with 1167 and 1003 respectively. Technology seems to have come a long way in the last 10 years or so. And its gonna get even better. I sure would like to be BnG's age and know what I know now.