I've been hiking Mt. Whitney the last several years using the same two day acclimatization plan (before it was just 1 day). The first three years I would sleep at Horseshoe Meadows and then at the Portal Family campground. However going from sea level to 10,000 feet is a little too jarring, especially trying to sleep in a tent. I sleep very little at the Portal campground 2000 feet lower, much less there (where it's often very windy). I guess if you had a nice camper with a bed it would make a big difference.

The last two years I spent the first night at Mammoth Mountain Inn (about an hour north of Bishop), which is at 9000 feet but more important is a full service hotel with comfortable beds to sleep in. The sleep you get two nights before the hike is gold, and fortunately I can sleep pretty good there and get acclimated at the same time. There are some good trails there but I've never used them (I think rest is more important before a big hike, although I'll walk up to the Portal store from the campground to kill some time). It's only a 2 1/2 hour drive from the hotel to the Whitney Portal, which you would do in the morning anyway. In my case it's very convenient because it's practically right on my way anyway (coming from the SF Bay Area).