We've stayed at the Hollow 4 times now. It's a laid back resort that is kept clean. The staff have been helpful when we contacted them. This isn't a big pool/activity place. But if you want a nice site, and don't want staff down your neck because your campfire is still going after 9:05 it might be the place for you.
Clean bathrooms and grounds.
Close to Waterville Valley and other White Mountain activities.