Thanks for the positive report, Steve!
I flew my RV-12 with the Backcountry Santas into Montezuma Creek last year. It was an amazing experience. It creates a real feeling of excitement for the locals who otherwise live in a fairly remote area. It's an amazing way to give back in a fun and meaningful way. Over the summer I flew to Blanding and last week I rode in a Kodiak.
The Backcountry Santa folks accommodate flying either into Blanding, Utah or one of the dirt airstrips (typically Montezuma Creek or Navajo Mountain) on the reservation; different aircraft and pilot capabilities are accommodated.
Please note that the Montezuma Creek and Navajo Mountain airstrips are on Navajo Nation property and permission is required from them prior to landing. Please respect their sovereignty.