Hi, well I'm not too sure. I've been bridal dress shopping with my sister this year and the one thing that i learned was: totally listen to the sales assistant in the shop - they are definitely the experts!!!
They deal with brides of every shape, size and age every day so they know their stuff. I'm sure there are exceptions but we found the level of staff in the bridal shops amazing!!!
I think the key is knowing your shape and feeling comfortable in the gown that you finally settle on. Apparently the perfect dress chooses you at the end of the day so there's no need to stress too much about it!!