It's a well made product.  Everything fits in easy and there's ample room so it's hard to overstuff.
I'm planning to upgrade my phone to iPhone 5, and they are slightly longer than my current iPhone.  The iphone I have now fits so perfect that if it was slightly longer, the button won't be able to snap down.
Although it's a great product, make sure it's compatible with your phone first.  I'll post a follow-up to this review as soon as I get my new phone and test to see if it fits.

Update:
Nope, Iphone 5 does not fit.  The button doesn't snap closed while tucked inside the sleeve.  But it's okay because the fit is so snug that you don't need to button it down.