Thanks for the all the info and suggestions, well, the sensible ones anyway....Orange Five yeah, got one of them
As far as comments about the strength of road bikes go, I'm not too worried about that, it's more the comfort side of things I'm interested in - oh, and before anyone tells me to MTFU, I don't feel the need to at all thanks. I'm 50 next year and my body is feeling the effect of years of biking, running, climbing etc., so I think I'm due a bit of comfort
I can appreciate what people have said re: steel vs aluminium. FWIW, a few years ago I made the mistake of buying a cheap & stiff alu framed road bike, after having a demo ride of a very nice (& £400 more) alu Bianchi - the difference was like night & day, and I sold the cheap bike after a few weeks.
Thanks also for the gen on tyre width and bike fit. The importance of the fit of the bike was something that I had forgotten about, as I'm in & out of the saddle like a yo-yo on my mtn bike.
Hmm...lots to think about. A friend has just emailed me with the address of a good 'roadie shop' in Sheff, so it looks like I'll have to bob in there and get some fitting advice. (Not sure if he does Spesh, but the roubaix sounds v.interesting)
Anyway, cheers for the feedback.