Does anyone of you have any ideas on what to get?
get the fastest processor you can afford. the 17 inch has one perc that none of the other models have - express card - which means more connectivity on a separate buss. my mbpro has this (older genertation) which i have a card for an addtional firewire buss, very nice feature. The 17 " is big.
Will the Macbook Pro be able to handle my needs?
in short yes but depending on how much ram and how fast of an internal drive you have your mileage will vary.
On my 15" mbpro 2.5 ghz core 2 duo, only 2 gig ram i can get 25- 30 vst synth tracks and lots of pluggins before i have to start increasing latency but i also tend to be non-committal till the end of project and use my cpu limit before using my drive limits.
]What kind of soundcard should I go for?
personally im very happy with my fireface and i find firewire very robust but the protocol has a shelf life. - there are dual port options like the fireface UC and the motu
Why should I go for a Mac for my musicmaking?
this is a personal choice depending on how you work. i ve been a mac user for years and im familiar with the OS which makes my work flow smoother. when i started i had no experience with the nuts and bolts of windows and i knew that would be a lot of work, time ( and frustration ) to have a competent knowledge of the inner workings of the hardware and software for a smooth working daw.