I moved from nokian 18s to sottozeros 19s. Sold old wheels. For 991 the winters are 20s. Anyway sidewalls are low versus any SUV, same extra caution is required with 18 or 19 or 20 on slippery roads.

 

I just posted in the Winter Warrior thread. Drove my 4S on 19" standard width Sottozero's through a major Montana blizzard. I've never been satisfied with their snow performance and this reinforced my conclusion.

Sottozero's are great in cold, dry weather and even cold, wet conditions, but they aren't designed for, and don't perform well at all in real winter driving conditions.

 

+1

They aren't great in fresh snow. I think they are very good on cold, dry roads.

I just had a set of Michelin Pilot Alpin PA4 tires installed on my 991. I'm looking forward to trying them in snow.

 

You should get a chance this weekend.

They closed the lifts at Whitefish Mountain yesterday due to cold. I heard Colorado will be getting some winter now too.