Computer comparisons are always difficult, with that being said I'll try and explain what my son (who is microsoft certified) tells his clients. It depends on the usage, will the programs you want in your system be compatible with MAC or Windows operating systems? You can have Windows installed on a second section of the hard drive of a MAC allowing you to run both types of programs, essentially both in one computer. Both operating systems can get viruses. Son's personal preference is for a Windows not Mac mainly due to the repair requirements are mainly brand driven with MAC but more easily done with a PC.