You should try it, you'll have a great time! (no, I gotta work)
A ride like this will have your legs sore a bit on the last days and after but it actually feels good, that sore leg feeling. Doing a century is much harder, no rest stops set up and a race format. With a good group a century is a +/-5 hour workout from hell. On a ride like this you've got 9-10 hours to cover the same amount of territory, you can zip along or cruise at a leisurely pace. Race between rest stops is what me n my friends always did on charity rides in Tx.
Check the route and the schedule to determine how much of the day you have to complete each leg of the journey, it's a long ride but fully supported and without the clock whipping your backside it can be a real nice lil vacation.