We've stayed at both.
Yosemite Pines can be tight depending on where your site is. The upper area toward the back seemed to have bigger sites. Granted the roads were rustic (dusty), the pool was clean, the playground for the kids were well done, petting zoo area for the kids and the on-site gold mine were a novelty. If you have kids, this would be the place to stay at.
High Sierra is tight but quiet. We found the sound of the creek at night drowned out just about everything even though the park is right off the main road through town. I don't think we'd stay at anywhere else closer to the park.
Gotta realize these aren't 5 star destination resorts.We stayed at those places to spend most of our time in Yosemite, not in camp.
