At some point I'd like to hear a modded 800 but I doubt that it'd get me to buy another pair of Senns. Sure, they're technically better than the Grados that I own but at this point I'm in it for the fun of the listen and the HF2's provide plenty of fun. Someday I'll get the stax rig back up and running and that should cover the accuracy portion of the equation.
Dinny,
Just enjoy the beautiful, beautiful music.