Weddingbee boards

Hello everyone...

I needed everyones opinions with the Bridesmaid dresses i've fallen in love with.

Here is a little about the wedding:

-Mexico in January
-Casual, trendy, elegant style
-we're super fun people
-main colours are green and bright purple with small touches of orange
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Now i was hoping for different styles of purple chiffon dresses so my girls can show off their style while still being comfortable... only problem is that all the dresses i've found are over $200 before alterations and all my girls are on a budget and i love them so i dont want them to go broke over this (on top of it, i'm asking them to come to mexico for our day, they're so sweet)

So down to the nitty gritty... I've decided this isnt possible and am going to go with something a little different. 
Ladies, check out this dress and give me some feedback.
I will shorten this dress to knee length and allow my bridesmaids to accessorize as they wish... they will also carry green and white flowers with purple touches.

Thanks!

 http://www.urbanoutfitters.com/urban/catalog/productdetail.jsp?id=23474166&color=001&itemdescription=true&navAction=jump&search=true&isProduct=true&parentid=W_APP_DRESSES

Also... Do you guys think once all dolled up with their hair and makeup done, these dresses wont look TOO casual?