Coming Back To Mac Os - Some Questions Options

[tribbles]

After being away from the Macintosh platform for far too long, I've decided that I'm now at the point where it would be practical to switch back. At the moment, I'm considering purchasing a 2.1 GHz iMac G5 with at least 1.5 GB of RAM. I would primarily use this computer for either Garageband or Tracktion, along with sample libraries like Ivory and Garritan Personal Orchestra and my MIDI controller. (I'm a composer. I probably won't be doing any live audio recording.)

The only real concern I have is in regards to the iMac's on-board audio. On my current PC workstation, I have to use a M-Audio AudioPhile 2496 to get decent latency using ASIO. When using the on-board audio, there was always far too much lag between the time that I pressed a key on the MIDI controller and the time that I actually heard the sample triggered.

However, I can remember that even back in my System 6 days, audio features on the Macintosh was always a cut above the competition. Do any of the experts here think that I can get decent latency with the iMac's on-board audio?