Which BM Dress

So I ordered 20 dresses and I have 4 bridesmaids, we're all going to get together next Friday. They will try them all on and we will collectively make a decision. I need advice of which way to sway them...

I have to preface this by saying that 2 of my BM's are my younger sisters and FH's sister is too. My MOH is the same age. So all the 'typical' BM dresses look bad on them since they are all so petite..
My sisters are 14 and 19, FH's sister is 22. MOH is 25.

Wedding is a night wedding Sunday of Labor Day at OFC, I want the wedding to have a vintage simple elegant feel..

1st: Bloomingdales - BCBG (looks a lot shorter on model than it is)

My opinion: It's cute and I like it but I'm nervous that it's not dressy enough and the little part that sticks out will be sewn down.
After sale it was only $70

2nd: Amazon - BCBG (I like it but it's a little shiny)
My opinion: it's cute and I think it's dressier than the first one but I'm nervous about it being too short...
$65 w/free shipping

3rd J Crew (might be too conservative) I just ordered it yesterday so I haven't seen it in person yet..