Tim,
Sorry for the pun, but you’re comparing Apples and oranges. Axio and Axio LE are hardware-based NLEs, FCP is a software based NLE. What you will find is that computers are becoming so powerful now that the difference between software-based editors and hardware-based editors has blurred somwhat and is not nearly what it was just a year or two ago, nonetheless there is a significant difference.
Realtime performance in FCP means that you can essentially edit several layers of video without rendering while you work, but you must eventually render. Realtime on a hardware-based NLE such as Axio is, for the most part, really realtime, and the rendering is not necessary at all.
What you will find when shopping for a MAC is that, unlike PCs, MACs have fewer options. They are essentially all built as serious workstations, and instead of having to worry which models are capable of running the apps you need, it more of a question of how much you want spend to make it work better. Any modern MAC with dual procs and 4gb of RAM can run FCP well, but the faster the procs the better. In the future, video cards will play a more important role as onboard GPU processing becomes increasingly powerful, but right out of the box every MAC is very capable of running FCP.
DRW