I worked in a camping store and sold water filters for 12 years. Hands down I think the best filter is the MSR Waterworks. Most people get sold on gallons per minute and # of gallons before a filter change. They don't realize that in order to move that much water through that fast the pores in the filter have to be larger and that clogging is actually a good thing and means your filter is working. A fiberglass or paper cartridge will eventually clog and then you'll have to hope you brought a spare with you. In the case of the MSR filter, it is made of ceramic and when it clogs all you do is pull it out, scrub it with an included green srubbie pad and pop it back in; good as new.
I've had mine for years and it has never let me down. I've had several PUR brand (Hiker, Scout, Explorer) crap out on me during trips.