A chemical treatment takes time, iodine has a normal treatment time of
20min. Unless the iodine is in the water that long it is not dead, just passing thru an iodine bed will not kill the cooties.
IMO
The best bet going is the hollow fiber type unit, IIRC Sawyer was the first but all the major's have one now and all likely made in the same room. I bet hollow fibers are at the heart of the newer LifeStraw.