Stuck between the Zpack Ultra, Outdoor Vitals CS40, Durston Kakwa 55, and Hyper Light mountain unbound.

Hey everyone!

I am currently in the market for a hiking/camping backpack and I know I want to go ultra light. These are the top backpacks everyone is raving about. Excluding price. I want to know everyones opinion on the comfortability, durability, water resistance, and which overall backpack people trust. Thank you in advance for any information!