I wanted to go there a few years ago. I am quite experienced with narrow steep roads, chose a Tuesday morning to minimize possible traffic, and found swarms of apparent locals zipping around in little Subarus not knowing or caring about the policy that uphill traffic has the right-of-way. I hate to think what it might have been like on a busy weekend!
I was NOT having fun, turned around and went down to Bonito campground. Lockett Meadows is said to be a wonderful place, but I guess it was not meant to be my place.