BBB is a butt ripper. I'm a flatlander and didn't make it on my first attempt last year. I've got some unresolved issues with Hogpen that I intend on getting straight this year.
I'll throw out a few more centuries worth the drive.
http://www.waynetourism.com/spar.htm
http://www.jimkrusecentury.com/
http://www.bicyclesavannahllc.com/
http://www.azaleacitycyclists.com/century/
Ride em all if you're feeling froggy. Just have fun......and ride a lot before BBB or 6-Gap if you attempt either one.
Michael