Few things are a lost cause, especially when it comes to national forest campgrounds.
Perhaps you've already been there, but if not, click on the "National Forests & Campgrounds" tab to the left and select the Inyo. By scrolling down the lookup table, you'll find in-depth descriptions of all the CGs you mentioned. We visited the CGs to survey them, but did not stay there. Of the three, I think I'd go for Mosquito Flat Trailhead. As can be seen by this picture from a campsite, the views are excellent.
As you'll see in the description of the CG, hiking is available to include access to the John Muir Wilderness.
I don't think you can go wrong with any of the CGs, but I'd like to add one to your list - Saddlebag Lake CG. Check out this view from the CG:
Awesome views from almost every site, access to Yosemite NP, hiking, fishing - quite a place; check out the description as above. I guess the one downside to this CG, is privacy between sites is just on the fair side.
Maybe someone has actually camped at one of these CGs. Hope this helps . . . Fred