Well, it will do what you want but of course the new macs have a higher front side bus and more level 2 cache I believe it is.
That extra oomph will make it possible to do so...But you will get that machine to do what you want it to...that mac can run quite a few tracks! Get yourself a firewire external drive for it and be happy! lol
Opus

$300??? Buddy, that's a DEAL! Add another 512Mb ram, take out the POS HDD that came in it and stick 2 Western Digital (WD800JB) 80Gb HDDs in it (the ones with the 8Mb cache). Take out the DVD-ROM drive and put in a Plextor 40x12x40 (PX-W4012TA/SW) ... yup, they work in a Mac! For around $800 you'll have a screamin DAW machine.

Hey guys, thanks for the input. My company leased about five of these Macs and they recently purchased one off the lease because it was easier than rounding up all the computers and returning them. I'm not sure what the street price is, but I'll get it as cheaply as I can.
;)

Just another thought for you if you decide to go the Mac route...
If you get it, and it comes with the stock Apple keyboard and "puck" mouse, you will be very unhappy with them. They are barely functional and lead to many frustrations.
I highly recommend the Microsoft Office Keyboard and Microsoft Trackball Optical as replacements. They don't come with the Mac drivers, but they're simple to download off of the Microsoft site. The added features make everyday life much easier. You'll find that maneuvering through your audio apps is much more precise and much faster.
IMO, these are two items that no Mac (or PC) owner should be without.