Very pretty! But yeah, it does sound like there might be an extra millimeter of space around the phone, which might allow it to slip out of the case when you don't want it to... You'd probably have to test one out before buying.

I should probably provide an update on my own PDAir case -- been using it for most of a year now, and it is holding up quite nicely. (I do treat the phone and the case with more care than most of my other toys, though. ) I'm surprised at how durable the elastic sides have turned out to be; they still hold the phone snugly, just as designed. And, as expected, a screen protector is advised when using this type of case; mine have already saved the screen from a couple of scratches.

Anyway, here's what the case looks like today: