I'd love to have one someday, but since they are so incredibly rare,I think I might build an a1200 full tower first. If I had the right parts, it would be almost as good I think, and somehow I always prefer custom builds.
But they aren't rare, they're sitting on a shelf waiting to be bought. Expensive maybe, but not rare. I bought three just last year!
Oh, and there's no comparison between a 1200T and a real 4000T. 1200T is a jigsaw puzzle of hassle, I was glad to see mine go.