Why Bejiita no Oji and not Vegeta no Ouji?
Well, Bejiita is the actual spelling for the character and Oji (according to our Japanese dictionaries) is the correct spelling for the word meaning "Prince".
When referring to our favorite snotty Saiya-jin on bakayaro onna's various lists she usually spells his name Vejiita.

What character goes through so many changes in the series? Our Prince.
We see little of his thoughts, fears, motivations and feelings in the manga and anime,
yet he has more depth of character than we see from ANY other character in the series.
For being such an alien, he is the most human character of them all.