I know, this is an older thread. Just wanted to add my CAD0.02.
I picked up a pair of the Heidenau K60 Sport M+S for my DL650 for this past winter. While I badly wanted the Silica version, they don't appear to have even close-to-acceptable sizes for the DL650.
I've done about 5000km on them so far, 3000km of that at well below zero. In general, I've been very happy with their performance on salty and salty-wet -16c roads. I've noted that they become hard-as-hockey-puck rubber at -20c, to the point of leaving black streaks on the pavement when you need to emergency brake.
Has anyone managed to fit the Silica versions onto their V-Strom? Did you go with the 100/90R19 front and 130/90R17 rears, or are more sizes available than are listed on the web site?
What about the other Silica winter Tyres available from Heidenau, like the K66 or K73's? Anyone try them?
What about other winter tyre options?