It was 105 when we pulled into Lone Pine so we opted for the RV Park instead. It worked okay and we needed the AC but I definitely wouldn't ever want to camp in a site that dense for more than an overnight unless you're doing Disney or something in a city (as we did the following several nights). We turned off in Hawthorn and came over the pass and down into Mono Lake, not really realizing the types of elevations we'd get into. That upper end of Owens Valley is some beautiful country so I'm not sorry we did it.
On the way back I woke everybody up at 2:00 am to make it a one day trip, and we went back via I15 and 93. Much better road with higher speeds but I'm not sure it was a whole lot faster. It was definitely less scenic. With stops it took over 16 hours but it was nice to get home versus spend the night along the way, and the wife and girls were able to sleep for a solid four or five hours in the morning before we stopped for breakfast, which made it a shorter trip for them. Plus no traffic pulling out of the city that time of day.