I'd say there is definitely a demand for such a place, just as there is for quality studio and recording space in general.
Have you thought about putting in a periodic advertisement in Criagslist? I don't know if you've heard of it...it's a networking/contact/classified-ad site rather popular in the US and Canada (headquartered in San Francisco, I believe), but they've gone international. I've never advertised on it myself, but I think it's free to advertise most things. Can someone corroborate that?
Here's the URL for the London site:
http://london.craigslist.org/
There are also specific sites for Birmingham, Bristol, Cardiff, Edinburgh, Glasgow, Leeds, Liverpool, Manchester and Newcasle. That seems to cover most of the island.