Where to buy uPVC windows online?

There are many online websites which sell uPVC windows, but finding the best out of the bunch is the challenge.

On a general note, A uPVC window that has passed a wide range of tests to get accredited by a well-known organisation is considered to be a good window. But to get the best window you’ve to find someone who has gone the extra mile to do something that no one else has ever done. Like windows that’ve been tested in extreme weather conditions to prove their worthiness. This worthiness reflects in the warranty the window possesses.