I've decided that we'll stay at Onion Valley instead, since none of us have been there.
Great choice. I did Kearsarge Pass as a warm up the day before I climbed Whitney for the first time, and stayed at Onion Valley before heading to Lone Pine and the Portal to start our trek. Worked out perfectly.
How big are the campsites at OV? Do you think we can get a 3 person and a small two person on one campsite?