Hi there (sorry for the long post

), just had my whole house fitted with new double glazing units. All Pilkington K glass with a mix of 6.3mm and 8.3mm laminated glass which I picked for sound insulation as I live on 2 busy roads!
The local company I got to do the job did not make the glazed units and I have loads of marks/scratches on the glass.I went round and marked all the defects I could see as they suggested. They came out today with a rep from the glass supplier and agreed to replace about 2/3 of the units right away (there are about 72 units in total). However we had some disagreement about what should be acceptable and practical manufacturing defects. Most of my complaints center round what I would call "squeegie" or "roller" marks which I gather is to do with their glass washing machine. There are other marks which look like greasy smudges often in lines or arcs and a fair number of scratches too.
The marks are extremely obvious in the direct sun but much less so in the shade and the supplier kept harping on about how the GGF test for acceptable defects was only in daylight and not sunlight. Surely the rules can't be so lax as to allow these sort of marks just because they show up more in sunlight? To me it looks like the units have been made without proper care to cleaning and the "washing" machine should not leave noticable vertical bands should it?? Hope to manage to attach a couple of images if it works, though it's not easy to photograph the marks!
I haven't paid them anything yet and feel like I want to ask them to use a different glass supplier as the one they have now has been so bad! Obviously this isn't possible and I need to give them a second chance but the rep kept saying that he couldn't guarantee the replacements would be any better, which really worries me.
I really need to get back to them tomorrow as I have currently reluctantly agreed to put up with a number of the faults as "acceptable imperfections"
Any help/suggestions much appreciated

thanks,
Nigel