No idea - whatever my hair will be when it's long enough to show a V or a U will be appreciated and embraced, lol. Never seen my hair long enough to know, so I guess the next year or so will be interesting.
I don't really have a preference on other people's hair. On my own, my fav shape is whatever way it grows. I hardly ever trim my hair (never have really) and only cut it for BCs (growing out color or relaxer) or the occasional search and destroy.. I barely ever straighten my hair bc 1% humidity ruins it immediately and I workout almost daily. When it's curly it doesn't matter to me what shape it is. So yeah, whatever way it grows is my fave shape.
I love the U shape... Even though mine grows into a V ( I think). V's are sexy but to me they give a "false length" impression, like the very tip could be waist but the vast majority of the other hairs are shorter... ( no offense to my fellow V's)
"V" - It's just cuter to me lol. It looks a lot more natural than the other shapes imo. Like it's how your hair would look if you grew it out long (and straight) without cutting it at any point or something.
I picked "U". My hair is currently in a "V" shape and I absolutely hate it. I am letting my hair grow so I can continue to lightly trim until that "V" is gone!
They all work for different people. I just prefer the blunt cut when it comes to length checks. It feels as if I'm cheating my way to APL, BSL, etc... without a blunt cut.