I have an uncle who is in the window business, and he said to me, whoever you get to put in your windows, don't ever get munster joinery. He said the amount of times they were called out to fix munster joinery windows is unreal.
Also, I was in my friends house this weekend, and he got munster joinery to put in windows a couple of months ago. They didn't fit the upstairs window right, and seemingly over the past 2 months, it destroyed the outside of the house. To be honest, I don't know the exact details, but the wall above the door had to be knocked out and build up again, all because muster joinery messed up.
Just thought Id tell ya my opinion!! Sorry for the rambling!!!