With regard to the actual chance of seeing one of these in the flesh as opposed to in a company spec sheet/brochure/web page (which from above it appears Ridgeback may have mis-publicised in some stuff) I may have made progress.
I popped into Balfe's Bikes in East Dulwich* and spoke to Dan (or some other three letter name - my memory for names is terrible) and it appears that he may get a couple of sizes in soon. Well he did phone to tell me so it's more credible than the old shop line about how they have just sold out, some maybe due next month, keep popping back...
Circumstances my end to do with purpose of the bike and storage mean that though I would very much like to see one the purchase of the exped bike will be later in the year (I was honest about this) but it may well be worthwhile for any other interested parties to get in touch with Balfe's East Dulwich and make it well worth their whlle.
It's a good looking well specced bike and apart from its possible use for crossing countries/continents is far more for for purpose for travelling across London than many other fanciful contraptions on the capital's roads.
* East Dulwich, south of the river, just south of Peckham, easy to get to from pretty much in anywhere in London by bike of course - handy stations East Dulwich or Peckham.
If Balfe's get some in they deserve to flog them to all of London - disappointing that no one else seems willing to.
As an aside, I learned in my searches (well I was told this by a staff member) that Evans, although a Ridgeback dealer, doesn't actually display Ridgebacks in any of its stores. They have to be requested. Very odd for a brand with a good pedigree of value and solid build quality. I was told that Evans displays the bikes its customers want/the most popular. From some experiences of Evans I cannot but suspect that the accountancy wonks choose what goes on the shopfloor according to other factors like margin/foor space yield etc. Why else won't you find the Etrex 20/30 in their shops?
http://www.balfesbikes.co.uk/pages/balfes_se22.html