This is the follow up shoe to the to the S-Lab Sense. I have the original and it has been a fantastic shoe. Pricey and not quite as durable as I would have liked. Well the new version is 20 bucks cheaper and suppose to be more durable. Weight has went up a tad but I don't think this should do too much in the way of slowing me down (I am already slow enough on the trails). The original weight 7.5 oz in a 11.5 and around 7 oz in a size 9 (but I saw it weigh it at below 7). This new one weighs in at 7.5 in a size 9 so probably around 8-8.5 oz in a 11.5 not too bad. They are suppose to retain their slipper like feel (one of the few shoes I can wear without socks) and 4 mm heel-to-toe drop. I will let you folks know what I think of it. The new black and red color scheme is cool. iRunFar.com has them in stock along with the new Salomon Mantra as well.