I have full winter tyres on my rx350, Nokian SUV WR3, Dont think I have see the traction light yet after three winters in the alps, Goes up the driveway in 6" plus of snow no problem and eats slush and deep puddles. Trouble is that they wear badly once the temp is above 12-15 deg. Remember that you need a minimum of 4-5mm tread for snow - In some countries it is "illegal" to have less than 4mm. Never sure about all season tyres always seem like the worst of both worlds.
Got them from openeo who I can heartily recommend, unlike most their warehouse is in the UK
Always liked the german winter rules that if you have to be rescued or cause a jam in winter conditions while wearing summer tyres you get landed with a big fine.