I had mine done by Classic Windows of Mottram (the one near Hyde) and I can't recommend them highly enough. I chose the firm in the first place because of all the 4 companies I asked for quotes Peter of Classic Windows was the only one to ask me what I wanted rather than telling me what I was going to get - showed me a book of photos of work he'd done, too, which none of the others did.
It was a good choice. The work was done quickly and efficiently, without fuss or mess and the cost, although not the lowest quote, was reasonable and compared favourably with the bigger companies.