I have the highest regard for all my 9 Bachmann 9F's and I cleared out all the Hornby ones later buying the Crosti as it is different, so I'll try one of the new Hornby's and see for myself.
Yes there seems to be something awfully wrong with quality at Hornby, I have just had to send my brand new City of Lichfield back to Hornby as the valve gear fell apart and the cab became detached from the boiler. So far my new Evening Star is working ok, but when I read your report I find it worrying. The pain of it is, because these models are so expensive now, to send them back you have to send them Special Delivery just in case they get lost.Just the other day my new Hornby 9F locked up, just had to ease the mechanism back and forth to get it to unlock, was not due to the valve gear getting tangled up but rather something inside, seems alright now. However for this price I would have expected better.
Here is 92194 prior tpo locking up