This was recommended by tech at REI over the MSR Mini because technology is "more advanced". Curious about difference regarding chemicals, doesnt seem that the hyperflow strains these like the Mini? surprised this isnt more impactful on Backpacker asessment.

Don't rely on any packable filter for chemical removal. The small amount of charcoal in the filter is no match for truly polluted water. It's only there to improve taste, and I doubt it even lasts very far into the rated life of the cartridge.

Hi there. There are certainly a lot of differences between the MiniWorks and the HyperFlow filters. Ignoring differences like weight (the Hyperflow weighs half what the MiniWorks does), pumping action (the Hyperflow is like a bike pump, the MinWorks has a handle pump), filtration rate (the HyperFlow says 3 L/min, the MiniWorks 1 L/min), and cleaning methods (the HyperFlow is a backflush, the MiniWorks you brush the ceramic), let's look at the filters themselves. The MiniWorks uses a ceramic carbon-cored filter cartridge, with pores up to 0.2 microns in size. The ceramic takes care of particulates, bacteria and protozoa, and the carbon core removes some taste-causing chemicals, such as iodine or tannins. The HyperFlow uses hollow fibre technology, which has a larger surface area for a given volume - this is how the HyperFlow can have such a high flowrate and be so small. The pore size is still up to 0.2 microns, so it's still effective for particulates, bacteria, and protozoa. The HyperFlow doens't have a carbon element though, so there isn't any removal of funny tasts from the water. As for whether having a carbon element is important - that's up to you, and where you'll be getting water from. Some peopel hate the taste of chemicals in their water. Many backpackers add chemicals to their water to purify it (chlorine/iodine), rather than remove them. Happy backcountry travel!

Neither will filter out CHEMICALS. The Mini might have a smaller pore size and is arguably more reliable, but you should be getting about the same quality water out of each pump. There might be less of a weird taste with the mini because of its filter type (ceramic) but that's not to say you won't be getting any chemicals that are in the water. I'm partial to the mini - I've had one for years and it's been great.