" My only concern with the chemical treatment / filter straw set-up is that you'd end up doing things in a somewhat backwards manner; you'd have to chemically treat the dirty water and then filter it.

For myself, I'd probably forego the filter straw and simply chemically treat the cleanest water I could collect with a simple pre-filter (bandanna, coffee filter, etc)."

You may well prove to have the best approach for me too, Denis. I'm going to give this combo a whirl for a while and see how it goes.