"Count me in the 'Mater camp." Tha gives no indication of what kind of vowel sound you prefer, Kim C.

I've always pronounced scone to rhyme with bun, the way my mother said it. Mind, I don't think I've ever met anyone else who says it that way. Maybe she made it up.

The variation in accents in England is remarkable. Arguing about which is the "right way" to pronounce a word is to miss the point. The point being, to hold on to the variety, while welcoming the fact that it does not get significantly in the way of mutual understanding.