Secondary double glazing of bay window, with acoustic glass

I was expecting Ventrolla to be expensive given their good reputation. But they were in the middle of the 3 quotes I got. The difference between their quote and the cheapest was small (but they were much cheaper than the top quote), and their product was the nicest: important as this is the downstairs front bay window. The sales, survey and installation and admin people were excellent. As for the effect: I’m a musician and wanted to reduce my noise going out and protect my piano from drafts. It’s worked brilliantly, and it looks good. (One of my students, an architect, was very impressed. As am I.