Just finished... nearly 7.5 hours... LOTS of wind, but still not a great pace (but keep in mind, its my "winter," I havent been riding much this year).
There was a guy on a mountain bike with (I believe he said) his uncle (maybe 65 to 70 years old) on about a 30 pound steel bike I met when stopping for water at mile 80... I struggled to keep up with them until about 92 and then had to turn off to a different path... FREAKING amazing!