I’ve used the Seychelle bottle filter for some years now (marketed in the UK as the TravelTap). Â It’s affordable and lightweight, giving around 1600 litres per filter. Water flow reduces towards the end of its life so you’ll know when it need replacing.
It’s a zero faff system with good flow and no need for pumping, squeezing or backflushing. I simply fill up the filter bottle and any other containers at the source, and decant from the dirty containers to the filter container as I go. There’s an inline version as well for bladder users.
Performance has been validated by a number of NGO tests and Government labs including the US Red Cross and the UK military.
I’ve had a couple of chats with the UK distributor DrinkSafe, who have detailed knowledge of the comprehensive Ministry of Defence testing (they’re a great company to deal with, by the way). Although many backpackers are concerned about the performance of filters with viral pathogens, the Seychelle posted very good results. While viruses are in theory smaller than the micron rating of the filter, it seems that in practice they are normally attached to larger particles which are filtered, so only minimal concentrations get through. The distributor also deals with Sawyer, and in his view the better portable filters should all be effective with viruses – it’s just that most of them haven’t been tested. It’s surprisingly difficult to find authoritative information on this issue, so I thought I’d pass this on for what it’s worth. Caveat emptor..
I put the Seychelle to quite a stern test when I was given duff information and was caught without water in an arid Karst area.  I was reduced to drinking from a blood-warm pool contaminated with cow-dung. No ill effects, though I now carry some tabs for additional peace of mind in extreme circumstances. I also do a lot of walking on Dartmoor which has fecal contamination from livestock and have never been infected.
Overall, I’m finding it a pretty good solution.
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