If you hunt with a buddy or a small group (2-6 guys) that share a camp or you suck down the water, I'd highly recommend checking out the PlatyPus Gravity Works Filter. Granted it's not the lightest (10.6 ounces) or smallest but I picked one up last year and it has forever changed the way I will clean water on the trail- 4 Liters of effortless water in under 3 minutes. The group I summer backpack with is a bunch of engineer gear nerds. All of them used to carry their own system until this gravity bladder system had i's debut. IMO worth every penny ($120 @ REI) and every ounce to have a consistant supply of 4 L.
I just picked up the Sawyer Inline and a Platy 3L big zip. Only played around with it at the house but I am sure liking it so far.
Always have the PUR hiker to fall back on if need be...