Yyy, you shouldn't be so overconfident, you have no idea whether or not you're better than us, or worse, you've never played us. ... That, and it makes you look like a n00b, no offense.
As I said, landing a fully charged Nuetral B will only happen if your opponent is an idiot or by some huge stroke of luck, making it unreliable. If something is unreliable, it's not good, none the less not a good combo. Just landing her Side B alone is easier than landing a fully charged Nuetral B, it defeats the point.
It's also not nearly as damaging as her other combos, so ... that combo's basically for an amatuer player. It's not a bad stepping stone for practice, but it's not practical at all in a real Brawl.