I now own four Rowena's because I evidently lack self control. Two of them are in the longer length and I adore that bit of extra coverage. I'm only 5'3" but I have a prominent back end and that tends to need a touch more fabric to feel like I won't be flashing parts and bits as always reach my arms up or carefully bend down to pick something up.
I know I'm a shorter woman so I recommend people taller than me choosing the longer length. Also I'm a firm size 14 or XL but for swing dresses I size down to L.