Katadyn Water Filter

I’ve been, for a while, looking at water filters. Well, just Katadyn filters. My plan is to get a katadyn for North American camping and a GE first need for international (first need filters viruses). I will definitely get the first need but I need help deciding which katadyn to choose from. There is the katadyn pocket, hiker, hiker pro, vario, and mini – however I do not know what would be the best for me. I will be doing a lot of purifying with this filter so I need it to be rugged and long lasting.
Help please?
Thx

Whichever gives you enough output for your needs in a reasonable time and and fits your size requirements for packing and the amount of cash you can bear to part with for the convenience of having one.
You only need one. No point getting one for home and another for abroad.
They all last OK if you take care of them. Treat them gently and pack them safely.
You can get spare cermic filters for them but if you take a spare one with you make sure it’s in a safe container so it doesn’t get cracked.
Here’s a bit about sterilising water…or steilizing it in the USA
http://answers.yahoo.com/question/index?qid=20110316183923AAR2217
http://uk.answers.yahoo.com/question/index?qid=20110604051711AAAfwor