STYLETHREAD -- LET'S TALK SHOP!

I remember that someone ordered this dress:

I've been eyeing it for a while but I'm a bit phobic about buying dresses w/o being able to try them on first.  I've never bought a dress from UO before, is this one TTS?  Is the material super thin? I'm pretty small-chested, is there enough elastic for it to stay up if I don't tie it as a halter?

TIA!