Having ridden for four incredibly hot and humid days in IA in July, I would never do it. It's also too large for my tastes.

Another option to consider is Cycle Oregon, which is held every year starting the second week of September. I did the 15th, 17th and 20th. Next year will be it's 25th anniversary, so they will undoubtedly be doing something big. The route will be announced in February and registration will open then. The ride has been selling out its 2,000 spots within a week. If it interests you, register first and ask questions later. That have a very liberal refund policy because there is always a huge waiting list.

At $850 for a supported camping trip, it ain't cheap. But the amenities and terrific, and riding in OR is amazing.