Good to see that you are pleased, I do not have a Mac Pro but rather an iMac and I know what you mean, I've described to people as a sense of stability that you can feel in the product, though I like your use of balanced, that really does describe what I think Apple has been striving for. So Macs I've owned have felt this way, others have not, my G3 is great and stable/balanced, my PowerBook G4, not soo much, still a good machine but it doesn't feel perfect.