FAST & EFFORTLESS
We used a friend's last summer, in a group of 4. It simply kicked butt. This filter cranks out so fast with little handle pressure. I have a Hiker (also had the older PUR Hiker) and I'm getting a Guide Pro because: The Guide pumps 1.5 liters pm while the hiker does 1 lpm (50% FASTER!). The Guide needs way less handle pressure than the Hiker. The Hiker is better than any MSR I've used and the Guide is so much better than the Hiker. Small negative is you gain 3 oz (11 vs 14) with the Guide. I'll carry the 3 oz extra any day when faced with 8 or more Nalgenes and a camp bladder bag to fill up. Best filter yet!