I used Jones windows systems (jws) I think they were in St helens, built me a porch and conservatory, did a great job, and always respond to maintenance calls quickly if you've a dodgy handle or stuff like that, I've also used safe style for French windows and they are a high quality, but you pay for that and you also have to put up with knobhead salesmen with the big companies.
Good idea for a thread this, I've been trying to get a decent pointing company for two years, builders just aren't interested in pointing.