I have several larger packs but I'm looking for a lightweight day/overnight pack. Maybe something in the 35 to 45 range. I've looked online at several but actual reviews are limited in this pack range for some reason.

Would be using it on long day hikes in the Rocky Mountain National Park or overnighters throughout Colorado.

Anyone have any experience with this size of pack? Example would be the Gregory Z35 to Mountain Harware Fluid 48.