Macs aint any better than a PC, in fact a PC/linux box would out perform a a mac pro, price wise etc for rendering.

But for the money I would go with an i7, with 12 gig and large storage accross multiple drives (with a SS for boot up) and a quadro card.

I looked at getting a mac a while ago and I wouldent bother unless you need to use a mac specific programme.