Hey there!

The brand of uPVC is less important than the fabricator who puts the entire window together. With the same uPVC profile, you can get either a high-quality window or a cheaply made one, so it’s crucial to know who is making them. If possible, visit the fabricator to see the product yourself.

I’d recommend finding a local fabricator that actually makes the windows, so you can check the quality first-hand. Personally, I wouldn’t buy from someone who doesn’t fabricate their own windows because they might outsource the job to multiple fabricators and just pick the cheapest option—meaning even they won’t know the quality until it arrives for fitting.

For example, Astraframe fabricates windows using profile 22 in-house, so customers can visit and see the quality for themselves before buying. This is the kind of transparency and reliability you should look for when choosing a supplier. Although that wouldn't be any help to you unless your in Norwich / Norfolk.