My Trek 1.2 weighs in at 19.1 lbs! You got bamboozled!

Will you notice the weight difference? Hard to say. You may notice a difference in acceleration if the wheels are noticeably lighter. A couple pounds of overall weight really won't matter much, since the weight of your body matters a whole lot more. Me, I'm losing weight. Down 10 pounds so far, which is going to make a much bigger difference than a couple pounds on the bike.