I have bought both of these for a very posh Thai dinner.
Dress code is 'ladies must be elegant and wear appropriate footwear'
The long one I've bought in navy with silver shoes & bag, it is stunning and well cut and flattering
The shorter one I thought might be more appropriate for Thai dinner, in the heat. I would wear rose gold shoes & bag
Another factor is that the boyfriend is wearing white jeans and a shirt and I don't want to look hideously overdressed