How long does activation for the iPhone 4S take (Virgin Mobile)? - 1

I'm buying a Virgin Mobile iPhone tomorrow, and I've heard a lot of conflicting statements about how long the complete activation takes. The website says-and I quote-"The process itself only takes a few minutes. Then, within 24 hours, we'll send you an email with instructions on how to program your Virgin Mobile phone number into your new phone".
Does that mean that it could take up to 24 hours? Or they'll just do it whenever they feel like it? Does it usually take just a few minutes, but they say within 24 hours, so you don't yell at them when it take 20 minutes, as opposed to 2 minutes?

I've read online about the activation issue some people have had, but most of them are from 2010, when the phone first came out. Has the activation improved any? Does anyone have any tips to get it activated sooner?

Added (1). There's no point in answering this question if you don't know about activating an iPhone. The iPhone requires a more rigorous activation process because it links up with your iTunes account. So there's a difference between activating an iPhone as opposed to a Galaxy.

Added (2). Does it make a difference if Radio Shack activates the phone? Will they even activate an iPhone?

I have a Galaxy S II from Virgin Mobile & it took less than an hour.

They usually activate it within the first 2 hours, but then again it could take up to 24 like they say