Well, had the C-tech charger on one battery for 3 days, and it never "fully charged"...second battery fully charged over night.
Pulled them out today, and took them to Battery Direct to have them load tested.
Yup...one battery dropped to 9 volts as soon as a load was applied to it.
Other battery held 11 volts with a 500 amp load on it for almost 10 seconds, and then went back up to 12+ volts when the load was removed.
Got one new battery for now, as I need to get the truck over to the shop doing the Line-X tomorrow morning.
Got the new battery under warranty. (Optima yellow tops)