I've done a few searches on the net since my original question on this topic. I was surprised to find a whole range of snow tyres from Michelin, Pirelli, Toyo etc in a huge range to fit all sorts of high power cars with low profile wheels. Looking at the tread patterns they certainly look suitable for winter use, although some of them didn't look to be much good as an all round tyre. The Michelin Pilot Alpin and Pirelli 240 snowsport both come in 205/45 x17 at just over £100 each.
Definitely got to get some for this year as the Pilots I've got on look even less snow friendly than the original Bridgestones.