Potential New Mac User with iMac question

[fiddler69]

I'm will be new to the DAW world. After much research have decided that PT is the way I want to go, and that MP will work well for me.

I have never owned a Mac, but I'm going to have a dedicated machine so I'm now researching the options of Mac vs PC. I like the idea that with Mac "PT just works".

I will mainly be recording actual instruments, vocals, etc. and not a ton of "electronic music". However, I do know that right off the bat I would like to use BFD or something of that nature - and I also like Ivory for some piano sounds.

With that being said, I know that it is recommended that some products like BFD, Ivory have their audio files also located on a separate drive. With a PC or a "big" Mac I see that being easy, what I don't really grasp is if I want to do that on an iMac then I have to use external firewire drives (I'm assuming here). So lets say I want:

1x Internal drive for PT, BFD, Ivory program files
1x Firewire drive for audio recording drive
1x Firewire drive for BFD, Ivory audio file storage

Is this practical? If I CAN do this, do I really want to? Or is the iMac not really what I need to be looking at?

Any input would be appreciated.