I just came back from a 3 day 2 night circular route with my daugther (8 years old) In the Pirinees all above 2000m. We slept in a tent and carried all of our crap by ourselves. I was basically repeating a route a friend of mine did like a month or so ago (4 adults, 2 kids I believe).
Usually the Pirinees is quite a humid place (in the way that you are crossing streams the whole time and water is abundant) but this year is being pretty darn dry, so the water sources are not so evident or clean. Until now I have always relied solely on purification tablets (Micropur Forte from Katadyn) as the water I gather is clean and debrish free (running water). HOWEVER, this year I was warned I might need to rely on lake/pond water, which is not my regular running water and can contain much more crap (animals using it as a water source).
Sooooooooo.... I bought a filter. I did my reserach and I knew I wanted a pump filter. I was set on the MSR Miniworks EX but I read not so great reviews and the ceramic filter seemed to clog easily and hinder performance. Some instances of the pump breaking also poped up in Google. So I decided to buy the Katadyn Hiker Pro instead (which is also cheaper).
I have to say that algthough bulky, the unit does not weight much, works flawlesly and has provided water for us both no problem. A bit tricky to manage the pick up tube in a clear spot (not rubbing rocks or bottom of ponds so as to not stirr the sediments), the outlet tube inside the bottle or water bladder and the pump at the same time. My daugther did a great job helping, althoug I also did it myself a couple times.
One thing to note is that the filter screws from the top and the screw threads only allow you to screw the filter so much before you reach the end of the threads and distort the plastic body. The oring does not seal properly and once you start pumping you see water and bubbles coming between the filter and body (and you don't get any in the outlet tube). Took me a few seconds to realise the problem. So do not overtigthten!!!!
Will post a few real pictures of us using the filter (captures from GoPro video) as soon as I process it.
Mikel