It might be hard to believe, but you can get better imagery than Google provides. USGS, as part of the National Map Program, has imagery down to 3 inch resolution if you live in an urban area (the wilds of Nevada, like the Sheep Range, might be another story, and it could be worse there if a big land grab withdraws much of Desert National Wildlife Range from public access, even worse than wilderness status which just meant you had to walk a long way).
This is one day's drive, with the 3 inch imagery at 50% resolution (top) and 100% resolution (bottom). Note that you don't see much area, the price of the high spatial resolution. The vectors show the morning commute (red) and evening (green), with the length showing the speed and the arrow pointing in the direction of travel. There is a point every second, and on the green you can see where I had to stop before making a turn.
This area has two roads, one NE-SW, and the other NW-SE.
Problems could be in the imagery (note that we see the sides of buildings, so there is some geometric distortion), or in the GPS. The GPS appears to be on the correct sides of the road on the NW-SE road, but is almost entirely in one late on the other road, even though I was always on the correct side of the double yellow line which shows up well at 100% zoom.
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