It's always reassuring to read a good review on something you just spent 100's of pounds on.
I find it interesting to note that the PSW4000 seems to be the sub of choice to team up with the 9000's. I was going to go for the 4000 but went for the B&W ASW750 in the end because it got rave reviews and little was known about the Kef PSW4000.
I may have to try and demo it to kerb my curiosity.