From what I know they started the Architecture course up at CSM just a few years ago, believe it is now RIBA accredited, CSM is an arts type of school, Jeremy Till (ex-Westminster, ex Bartlett) took over last September I believe. Think the course looks ok, students seem quite positive about it as far as I have heard, would be interesting to hear from any though, what their thoughts are. Don't think it is quite your usual modular structure most courses use, could be wrong on this though or some of the above info so look into it. Fairly mediocre grades to get in I think but probably not as low as UEL - University of East London. So reputation ok to fairly good I think, perhaps a fairly smallish number of students on course, not really got the 'name' branding of Westminster, Bartlett or London Met which some people are attracted to, not myself personally.
In any case I would say ID, PD and Architecture tend to be a whole different kettle of fish. Sure they're all design based but someone who is good at designing buildings isn't necessarily good at designing product or not as good and vice versa. With ID I think you need a particular interest in interiors, often people excel at designing exteriors, i.e. architecture but hold little interest in the interior beyond the floor plan, its a different interest thing, maybe a slightly different focus of the mind. Often Architecture students are asked to design interiors on the hoof with little training and the result I think are often mixed, often poor even as they have been given little training or time devoted to designing interiors. On Architectural Technology, CIAT courses there is often an avoidance of doing interiors which I believe is the best way. After all, they were split into several subjects for a reason, for efficient use of time and a different mindset I think, doesn't make sense to exhaust oneself treading on each others toes and risk a poorer overall result. Also if your naturally skilled in one subject area why waste time with other subject areas, I mean if your innovative in designing new products you can really cash in as they can be worth a mint when brought to market. Worth saying though that last time I looked most PD courses were hard to get into, high grades, quite a hard course perhaps.