Beware "Old Priest Grad Road" - west entry to Yosemite

The horror stories come from people who blindly trust the GPS directions, not from people who use it intelligently, and in conjunction with other tools.

With smart phone data, or downloaded maps, you can get the Google maps info along with a big "You are here" maker from the phone's own GPS receiver. GPS and digital maps are useful even if you don't ask for it for directions. And even if set to give directions, you can ignored them. It's a tool, not a boss.