I have all three, Kuiu, Kifaru and the First Lite. The Kuiu is the lightest, but most delicate and wouldn't wear it as an outer layer. The FL is solid, more durable than the Kuiu, but you still have to be cautious. The Kifaru is the heaviest, but also far and away the most durable. The Kifaru has added material to protect the high wear areas like the elbows and the pocket on the front is much roomier than both the others. They also go in the same order for warmth, Kuiu, FL then Kifaru being the warmest.