Bought for a pittance from Kernow Model Centre at the RMweb do, this is an interesting addition to my collection. A pre-production version of their excellent Beattie Well Tank.
Pre-production models are pretty rare. By definition there tends to be only one or two produced for each model, and they tend to be hung on to by the company producing them. Kernow had several examples in various stages of development and decided to sell them off in case anyone could think of a use for them.
I picked one of the most complete examples, it's got metal wheels and connecting rods, the body is largely as the final model would be. OK, there's no motor but it can be pushed along with everything working. I could couple it up in a train to be delivered, and if painted, you would struggle to tell I hadn't de-motored a "proper" model.
As it is, I've coveted Pat Hammond's prototype Triang and Hornby models so now I've one of my own.
If you fancy adding to your collection in the same way, I understand that Dapol might be offering some pre-prod models to their collectors club members in the future. Could be worth joining for that!