I've leapt in for 99k, and will post when they hit the Marriott account.
My one experience with Marriott was that I ordered a transfer to Tesco, but the system cocked it up. The very day I was toying with sending them an email to ask what had happened I quite spookily got an email from them explaining that they'd cocked it up and the points would be in my Tesco account quick smart. They were, and I was fairly impressed with that.