Water? Reverse Osmosis?

Should I be taking particular concern in what water I am using? I have not had a chance to test the tap water where I am, but I am sure it will be pretty crappy.

I know it should be around 6.8 Ph right?

So should I be looking to invest in a Reverse Osmosis system as I have read and been told that it is the best water to use?

IF so can someone please point out a website selling a cheap system?

I found this:

http://www.easyh2o.co.uk/category.asp?CategoryID=6&Cat=RO SYSTEMS

But have no idea which one to buy, and £150 kind of expensive for a little water filter or is it not? lol

Any help is much apreciated.

i second purewaterclub

Could you recommend which one to buy? Theres so many kind of confusing. Much cheaper than other sites, but Im sending to Uk so hoping shipping not too much.

Is RO water essential?