I once had to do software development in an open plan office with sales, business manager and someone from a different company in it.

Never again (it's actually a large part of why I have my own company), I actually threatened to quit unless I could work somewhere quiet (hell I'd have worked in one of the storage units as long as it was quiet).

I'm 2-3x as efficient in a quiet office where I can listen to music when I want to and have silence when I don't than I am in a noisy one.