ok. first off apolgies on 2 counts.
1/ they are
marked as M+S tyres despite my insistance that they are no longer so, must admit i hadn't noticed it of late.
2/ they don't
have BS numbers on. only "E" numbers now.
attached a few pics for you to see what to look out for.
pic 1 pirelli winter tyre
pic 2 avon winter tyre
pic 3 michelin winter tyre (complete with "E" markings)
pic 4 the difference between winter & summer tyres. the one on the left is an avon winter tyre, the right one a pirelli P zero.
the thing to look out for in the tread is all the extra little slits, called sipes.
at the end of the day if a tyre is marked up with the winter symbol which is now standard across all makes, has all the extra sipes in the tread then you don't need to worry about looking for the "E" markings as long as you are buying a known euro brand.
don't get me started on cheap chinese imports though..................