Firefox Adolphus! No problems with ICREW or TravelNet. The problem with MAC's is that when it comes to recurrent time, the A/C systems CD's don't run on the MAC. The FCCQ CD works with MAC, but not the systems. You can download Windows OS for MAC. From what I've heard it uses about 35 gigs of the hard drive. You can then choose which OS you want to run under the utilities function. Haven't done it yet, but planning on it soon.