Winning our Editors' Choice award, the Gravityworks churned up some surprising results in our lab. Taking the lead in our side-by-side tests when compared to other water filters in our fleet, we determined that it easily treats any amount of water, small or large, is incredibly versatile, and works well for a large group of people (or for a solo hiker on the move). Our initial thought was that this system would be too bulky and time-consuming for our quick pace, but we soon found out that this was the cream of the crop.
In fact, this one of the fastest systems for filtering water; it is the best option for filtering large quantities, is one of our lightest filter systems, and requires little to no maintenance. The filter lasts a long time before replacement (1,500 liters). The primary drawback to this system is that is more expensive than the average pump filter such as the Katadyn Hiker Pro or the MSR Sweetwater Microfilter. Also, it does not treat viruses like the SteriPEN Ultra or the MSR Guardian, so if you plan to travel around some very sketchy water, this may not be the filter system of choice.
This filter just barely beat out its closest competitor, the MSR AutoFlow Gravity Filter. This very similar system may work best for you, especially if you already have an MSR hydration bladder or Dromedary bag to use with it.