I just bought this dress at M&S. Mainly because it is cotton and I was delighted it was the right length (I'm 5ft 2). There were other dresses I preferred but were ridiculously long.
I'm not sure. It seems simultaneously infantile and similar to my mother's nightdresses. I'm 54. I like the fit though and the colour, I'm a few pounds overweight but I downsized a bit so it's fitted over the bust, like with the model. I think they intend it to be a lot more oversized than that - I bought a 6 which I most definitely am not.
I'll most probably keep it anyway as I don't have any loose dresses, but curious as to people's opinions.