Completely depends on your locations.
3 of mine I got within 50 km, really easy. Then two were single lane roads in the middle of nowhere. Roads went on for miles in each direction with nothing. No road signs. From vegetation/geography I could limit it to some degree, but they were still complete guesses. I suppose I could have traveled down the road until I found something that gave it away, but I don't think that's the point.
3
...
One of my spots had a second street view car following it for a long time.
Got 8278 points. Wasn't trying super hard (never zoomed in on the guess map to try to get real accurate). Only really messed up one badly. I saw people driving on the other side of the road and quickly guessed England, forgetting about Australia (which it was).
The OP even gave us a hint. My key to figuring out I was in Australia is if the signs were in English and there was any topography even remotely interesting to me on the horizon. Not sure how dense England is, but I have a feeling you can't drive too many miles without hitting a house or something. The red soil also gave it away.
