hi Busty,
I've had a HHKB (lite) for nearly 8 years now, and have loved using it with Emacs. It does work very well with emacs I think. Glad to hear that you are an ESS user - I'm one of the developers, and indeed my HHKB was used for almost all my elisp coding for ESS.
Just recently I found this forum as my HHKB lite was starting to play up, and I've been looking for a replacement -- they are no longer sold in Europe. I was thinking of getting a pro, but the new realforce sounds intriguing.
Also, whilst searching for keyboard advice, I was surprised to read that the old MIT keyboards (on which presumably emacs was developed in the early days), has the ctrl and meta keys around the spacebar. I've always just used the ctrl key to the left of A, and used diamond as the meta key, and stayed well clear of the alt key. But it looks like in the old days, the key closest to the space bar was ctrl, and then meta was the next key out:
http://www.johnbear.net/symbolics-keyboard-paper/gnu-emacs-kbd-for-mac3.htmlI've never tried this arrangement on the HHKB, but would be curious to know if others had.