(This is my 2nd attempt at posting this message, so if my first one eventually appears, please excuse me for repeating myself).
Thanks for your help and I have to admit I'm disappointed with the results, as I so fancied a disklavier!

However, I don't want to make an expensive mistake though and it's really important to buy the 'right' piano as I regularly hold Special Exam Visits at my home.
Indy and Jod - I like the idea of the Roland Edirol. I must admit I gave up recording live a long time ago due to the poor quality. Does the Edirol give a good clear result without picking up too much background noise? I tend to record on my clavinova these days, but the piano pupils find this hard due to it being a different 'feel' to the acoustic piano. I usually use my clavinova for silent practise or for the keyboard pupils as they love the feel of the weighted keys and the dynamic range they can get, in comparison to the so called touch response on the keyboards, which is not very good at all.
Roger - My piano tuner agrees with you, in that there is too much to go wrong. He particularly feels that recording a pedal action is likely to damage it in the longterm. Which Yamaha Grand do you like?, as it looks like I'll have to investigate the acoustic grands on the market. I have a Daewoo Royale which is not co-operating well, especially with the pupils at the higher standards. The tone's not very even and it's hard to play large chords with one sound (often 1 or 2 notes are not sounding). As for the younger players, they often get frightened by it's power!
Many thanks again for all your help.