I've never been a big fan of Yokohama's I find they wear very fast. Lots of grip in the dry though.
Are we now at the point we should switch to winter tyres weather wise?

I must admit my Yoko's that came on a new celica I bought went in no time at all but I bought some Yoko's for a pug 206 xtdt thinking the same would happen at £100 for 4 several years ago and they did well over 20,000 miles before I sold the car with still lots of tread left. They were deadly in the wet though :)
 
could be fun to start withthen ,,,,,,

have to see when hes getting more in to get rears done then itl be fun on my own but not when my sons in the car , although he likes getting the car /van sideways on the muddy field when i take him on his quad , he just laughs !

but not on the road where danger lurks
 
The trouble is, winter tyres on the back aren't going to help you with traction or control in snow and ice, which is the main point of seasonal tyres. You need them all round.