Hey Liming! For everyday use, abuse, and charging in the backcountry as well as occasionally in the resort I think the F1 is the better choice there. The Speedfit walks a touch better than the F1 but I don't think the Speedfit has that extra powerband to drive huge skis like the F1 does. Lynx compatibility with the F1 or Speedfit should be fine either way.
Hey Dgg! Should be a 2.5mm Allen Key. Just make sure it's really sharp otherwise you can definitely strip it out.
Hey Aaron! Not expecting to see any more before the season is up, unfortunately.
Hey Bruce! Nope, no cant cuff! They went light and burly with this one!
Hey Scott! Not planning on getting more in the next couple of days, though there are definitely kits available with more than enough length. Find them here.