I suspect it may be a similar situation to the Merino, which was imported in the late 1700's to improve the fleece of the Southdown. They couldn't cope with the English weather and were later exported to Australia where, of course, they did very well. I note the folks who paid a lot for them also keep alpacas, so are used to eye-watering amounts of money. I would feel very cautious indeed about importing sheep to the UK, given the problems with Bluetongue, Schmallenberg and so on in recent years.