In order to understand the HOLY QURAN and everything in arabic, that is why I study it, but frankly speaking I don't prefer any dialect ( and I don't understand any of them), because, in my opinion, if you don't live in an arab country, you don't need it at all). For example, I have some female pen friends: one of them is from Tunisia , the other one is from KSA, sometimes I chat with sisters from Egypt, so, which dialect should I study?)))

To understand the Qu'ran

I am learning the Classical Arabic to be able to read and understand the Holy Qur'an and all branches of the Islamic Science; and egyptian dialect specially because I am going to study Islam there very soon in shaa Allah, I like the country and I have many egyptian friends.

Cause it's awesome i think :p 

but israa arabic is not so easy for foreigners  it's so easy for us