I have a PC running iAtkos ( have an OSX License but PC Hardware) but I also run Linux and Windows since I need to support all 3 platforms for the company I work for. Really besides OSX the hardware on Mac and PC is not much different anymore since they are all using the same processor cores. Also Mac is just as prone to attack as Windows there was just a group that won an new Macbook by using a zero day issue in safari to gain control

Safari/MacBook first to fall at Pwn2Own 2011 | ZDNet

make sure to keep your antivirus and spyware applications updated on Mac just as much as you do on Windows.