Iphone 4s getting the ios 7?

So I'm getting the iphone 4s tommorow, brand new and I really want the ios 7 feature and update. Is it smart that I download it right away when I buy my phone or later when I have a few things installed like my mail, contacts, facebook etc.

I think it will already come with it on it.

So installing iOS 7 on a iPhone 4s might make it lag. Reports around the internet have confirm that this will happen.
It does not matter if you do it right away or later, just hear in mind the lag that will come with iOS 7.

Iphone 4s now comes with ios 7, so you won't have to worry about that.