Just seen this thread…
I use a MacBook Pro for all blender modelling work, i7 processor, 8Gb RAM, very good for all my projects so far including file sizes up to 166Mb, not tried bigger as this is the biggest file I have. For rendering I use an Ubuntu box with a 6-core AMD processor and a 4GB GTX980 graphics card. I don’t get using a Mac mini for rendering, it doesn’t have the grunt of a GTX980 and will probably get too hot. I have a liquid cooler for the CPU, not needed for GPU rendering, but useful for other things the machine does. Incidentally, whilst I have good fans in the box, I leave the back off so it never gets too hot. On my MacBook, I sometimes render smaller jobs, like video from png files, here the Mac used to get too hot, so I installed Mac Fan Control:
to keep everything cooler, this works well.