Hi there, I use a mac mini as my main system for recording and i absolutley love it
. I've never had any problems mines is the earlier 2009 model (the one before the one just released). I run PT 8LE alonf with Reason 4 and it handles it great and it can take very large sessions e.g. multiple Instrument tracks running rewire multiple audio tracks and several plug ins and still run smooth.
As for the fan I actualy barely ever hear it
It is a nice little machine