I bought a MacBook Pro just for Scrivener.
And that’s all I use it for.
I have Airport disabled by default, and I treat the computer like my old Royal typewriter. One machine, one purpose.
(ok, I have installed a printer driver too)
On my everyday Windows box, I use a great app called The Journal for dumping and organizing all the bits. It exports entries as rtf files and I then transfer those to the Mac by flash drive.
Why a Pro model? For the beefier video card to drive a 20" monitor. I also use a cordless logitech mouse and one of those newish little cordless keyboards that Apple makes.
There now.