Moonshine, re the Sie check dress, size up is my view, especially if you are busty. I have the 14 which just about fits at the waist even though I am a 12 in other styles and occasionally even a 10. it is very similar to the purple patterned dress of early spring which I couldn't get to fit me even in a larger size but which looked fab if you could (I think someone on here bought it for a wedding or special event).
It is a beautiful dress: I haven't worn it yet but autumn is well and truly here so it will be getting an outing soon.