I am in the exact same position myself. I have the staggered 19's and am looking for an all season for snowboarding trips. Funny enough mammoth and big bear are mtns I go to as well. It seems like its between the Michelin Latitude HP Tours or the Pirelli all season that is up on tirerack. My dream tire would be the Continental DWS but as you probably know that is not made in our size. I will be curious to see what you decide. I think with the options available the Michelin might be the best choice.