Well Richard made relatively few of them - I think a couple of hundred pair, made when they were up to date on their 2 deliveries and had the time. His initial thrust was good sound for reasonable prices and I think his approach of putting 'socks' over a framework instead of wasting money on aesthetics with fancy veneers etc. was brilliant.
His speakers have always had pretty good mid range, but were perhaps a tad loose in the bass. He first addressed this in the 4 and 4A, where he used bass drivers bolted together face to face and separately amplified - I have his stand alone cross over and a pair of mono amps dedicated just to the bass (see them in my old listening room if you are interested - http://i888.photobucket.com/albums/ac81/wspohn/system3_zpsqdymqrth.jpg They look like the 2s on steroids.
He continued on from there paying more attention to bass, which resulted in more expensive better sounding (top to bottom) speakers. He's also gone for improved aesthetics, presumably on the theory that anyone paying the necessary dollars for the bigger speakers will also want them to look better (the 7s look kind of like Wilsons).