Vocaloid covers vs Original versions

(Before I begin it: I don't want to insult any Vocaloid with this journal entry. I only did as trivia.)

Okay, guys, I currently listening to Vocaloid-made songs. (Hehe, you didn't realized this about me, right? ) But I found some covers were made with this program and brought some of them as a collection. Original versions are included too. Do you think which version is better?
I put it as one cover per Vocaloid.

So here it goes:
Breaking the Habit (cover by Megurine Luka, original made by Linkin Park)



Higurashi no naku koro ni (cover by MEIKO, originally sung by Shimamiya Eiko as the opening theme of When they Cry: Higurashi's 1st season)



Judas (cover by Hatsune Miku, orignally sung by Lady Gaga)



Turn me on (sung by Kamui Gakupo, originally made by David Guetta and Nicki Minaj, first version put to the official lyric video)


 
Katayoku no Tori/One Winged Bird (cover by SeeU, originally sung by Shikata Akiko as the opening of Umineko no naku koro ni; you can hear Shikata-san's vocal on the background, and I put the shorter version for the original )