£1200 Road bike - should it be fully carbon?

um. compared to a really quality good steel frame, ride quality can only get worse. but you get a lighter (and sometimes more responsive) frameset. That might or might not melt in the sun.

Couldn't agree more. I must admit to liking the carbon forks on my road bike, but the frame itself is 631 and comfy as fuck, despite 700x22 tyres at 130psi and bloody stiff wheels. No doubt one could build a carbon frame that comfortable, but it'd be a custom job which would cost more than the framebuilding course did (and be more vulnerable to crashes, and harder or impossible to repair, and unlikely to last as long). Weight saving is always nice, but the frame isn't a huge component of overall bike weight anyway, much less of bike+rider weight.