Hi all,
You know, I'm actually going to say the '020. Back in the day everything was running on a 68000 (Atari/Mac/Apollo etc.) and when the first CSA 68020/881 tower was released it brought the power of the little A1000 up to that of about a Sun workstation costing WAY more. Software like Silver! and Sculpt3D really flew on those beasts. The '030 was an incremental improvement anyways. The '040 brought the FPU integration and some kick-ass FP performance. The '060 doubled that performance again. But, it was the leap from 16/32Bit to full 32 bit with the '020 for me that was the most memorable... {sigh}
My 2 cents (Canadian)...
-G