Yes, I have the 20p too (also warped as I said) so I agree, why not.
The seller told me it was plastic but it is the usual "clay" material (which I was pleased about) that I thought it would be.
Pity about the condition but at least it gives us another to llok out for.
I just wish I'd won the London 50p without inserts I saw a few years ago but missed out. I hope it went to a good home but not on the guide or in the book so..............
Thanks again, take care.