I've done quite a bit of research and have purchased the maps book as I'm planning on doing route 3 toward the end of August. The maps are excellent and highly recommended. I ran across a trip report on the Toyota FJ Cruiser forum:
http://home.comcast.net/~j.agent/obcdr.htm
These guys did route 5 from Lakeview to Union. It took four days and the only human contact they had was one lone USFS lookout station attendant. Some great pictures.
Again, if anyone has done any of these routes I would love to hear about it. I'll have a full report on route 3 in August.