Yes, I have a sonnet tech ATA133. I have never heard tha there was a limit on drive size on the native ATA channel. In fact the drive works perfectly on apple hardware. Once the firmware was installed the drive worked flawlessly.
BTW the LaCie 500gb drives are multiple drives stitched together to form one biiiig volume. Not a terribly good idea, since you double or triple your chances of the volume failing.