I have a few years old Blizzard G-Force Supersonic in 174 cm with bindings they weigh 13.3 lbs (this is for the pair of skis). I just got my new 181cm Blizzard M-Power 8.5, they weigh in at 15.8 lbs. Maybe 2.5 extra pounds is reasonable for the extra 7cm in length, they are wider at 85 mm vs 74 mm and they M-Power's are full suspension vs partial suspension in the Supersonics. The bindings are both Marker bindings specifically for Blizzards, but the DIN goes up to 12 on the Supersonics and 14 on the M-Power's.
After describing all these differences, now 2.5 lbs doesn't actually seem as odd as it first did Any thoughts?