Assalamu'alaikum W.B.T. & Hello..
Narrated Abu Huraira R.A: The people of the Scripture (Jews) used to recite the Torah in Hebrew and they used to explain it in Arabic to the Muslims. On that Allah's Messenger S.A.W said, "<b>Do not believe the people of the Scripture or disbelieve them, but say: 'We believe in Allah and what is revealed to us.</b>'" [sahih Bukhari 6.60.12]
Also refer Quran [3.84] & [2.136]
As muslims MUST believe in the 4 Holy Books, it's one of the 6 pillar's of <i>Iman</i>. so, I personally believe it's dangerous to belittle the other Holy Books, as we are not sure ourselves, wether the ayat is the valid ones, misintrepreted ones or distorted ones. The main thing is, we must belive in the 4 Books (it's true meanings), & follow what is revealed to us -- The Quran.
wallahu a'lam. Do correct me, if i'm mistaken.