Terrapin,
I've picked up giardia twice, once in the Q once in BWCAW.  Near as I can tell, the first was from swimming in Shade Lake near a much used campsite and the second was probably cross contamination from an inexperienced friend not using a filter properly.  Not much fun either time.

Regarding the rest.  I used the Hiker for years until mine cracked last year (it cracked along the pump cylinder and created the best squirt gun I've ever used).  I bought a new one, thinking that my old one had lasted about 7 years of hard use.  My new one, with more fancy bells and whistles (mostly the hose connectors) actually cracked in almost the same place within about two weeks of use.  When I inspected it, I discovered that the new model is cast as two pieces and (presumably) epoxied together.  The seam actually runs along the pump cylinder and, apparently, the pressure forced a split in the seam.  I returned that one and picked up and MSR ceramic filter pump.  My friends have used them for years, but mine seemed to require filter maintenance after every liter and drove me nuts.  I picked up a Basecamp for a 12 day trip with a friend.  We liked it, but it did slow down by the end of the trip (it would take an hour or more to filter 92 oz).  I use collapsible Kanteens from REI (92 oz) to filter into and they work pretty well.  They stand up okay on their own, but I usually brace them with a rock or against a tree, etc.  I will use it again in the future, but I will always carry a hand pump, as well, to use during long days or for a quick liter or two.
GP