Finished the 7th book last week. The Crimson King and Mordred were both huge letdowns. The ending wasn't great, and I am still working on digesting it properly.
There is one thing though that still irritates the ---steaming pile of meadow muffin--- out of me though. In the keyworld, time only moves one way. At any time in the other worlds, be it other earth's or midworld, the time is always the same in the keyworld. King hounds this fact over and over and over... when it later serves his plot.
How then, did Susannah go to 1999, and then Roland/Eddie go to the 70's? Nevermind the fact that many people debate the validity of the overall ending based on this fact.