In reply to the livery query, the link below contains an image of "Claud Hamilton" in 1937.
Though not the best quality, it shows the loco in much the same state as Hornby's model, complete with shaded numerals and lettering, albeit maybe a little finer.
As for my model, I ran it with a train of (anachronistic) Thompson suburban "teaks" for about 2 hours on the Model Railway Club's test track last night. It performed beautifully and I am very pleased with it.
I had already purchased an LNER black Claud last year but was eager to get this example. It wears a similar livery to the loco shown in my avatar, a painting by my father of a "Royal Claud" (one of the versions with a decorative valance). The protype also provided me with my RMWeb nom de plume, and in my opinion is a particularly handsome engine, perfectly proportioned.
It is a great shame none were preserved: an MRC member explained to me that one had been marked for preservation at Stratford, but on one side only and the scrap team approached from the other side...
The group building a new one have started work on the buffer beam.