I have modded a lot of "brand new" speakers and they rarely sound any different from "old" speakers. I think the belief is new drivers are tight and need to loosen a bit, and this may indeed be true for really new drivers but the truth is they often are not.
I had a guy send me "new" 1.6's (just purchased) this past year and he phoned magnepan with the serial numbers and found they were made in 2002. That means they were sitting somewhere for 7 years, so I am sure in that time the driver "relaxed". I know I would have.
That said from what most people say 20-60 hours is all it should take to "loosen" them to full extension. The XO will take longer.
It's all about the music...