The new model of a mobile phone with the mp3 player will be a huge commercial success.

Hello.

Please have a look at this sentence:

The new model of a mobile phone with the mp3 player will be a huge commercial success.

a) Is it grammatically correct?
b) Especially, 'mp3 player' sounds general so isn't it better to use 'an' instead of 'the' before it?
c) Would it be the same if we replaced 'The new model of a mobile phone' with 'The new mobile phone model'?