Best filter EVAR!
I LOVE this filter. I had a Katadyn base camp filter, but couldn't get a good seal where the filter attaches to the bag, so returned it. The platypus filter though, I've loved from the first moment I used it! I usually leave the 'clean' bladder at home, and just directly fill up my bottle/bladder in my pack - which means the filter weight is right around a half pound.
We took this filter to Nepal last month on our Everest Base Camp trek, and it more than paid for itself by allowing us to filter water rather than have to buy bottled water the whole way up.
If and when my current one dies, I will be replacing it with another.