Ok, GREAT information everyone, thanks. Here's what I'm thinking of doing, see if my reasoning holds water <img src="/images/graemlins/grin.gif" alt="" />

Katadyn Hiker Pro or Guide Pro (preferably, but it's not listed on the Katadyn web site) as an everyday filter for hiking, camping or bug in/bug out. Micropur tabs for purification when hiking light. MSR Miox for purification on long term camping and bug in/bug out. Bleach and iodine at home for long, long term bug in.

It seems that some people have gotten lucky by filtering with coffee filters or bandannas, and by not purifying in most situations. I guess I'm paranoid enough to do both, or at least have the capability to do both.

Does this sound like a good plan covering all bases?