The American market is certainly stronger for small bores.

Collectors like to buy toys they don't have and most have a nice 12-bore as more are available.

They all start looking for the smaller stuff and there is less of it about so it sells faster and for more money.

I have no time for the small bore fetish personally. A close to 6 3/4 - 7lb 12-bore was made in far higher numbers than anything else for a reason - it does the job better. i'll get my crash helmet!