We're creating some opening HD footage for a skating bid in AE, FCP, Motion, LiveType and Electric Image.

I've been recording out to Master Sony DV tape.

Yesterday, I grabbed some older, no longer needed tapes with some DV footage. Not Master, but good Sony tape.

Played out the recorded footage we created, and the tape played a little further on our 50" plasma out the component port of the Z1U, and the DV footage looked really good uprezzed.

Nothing technical here, but it was surprising

That would probably have more to do with the scaler in your HDTV. When playing a SD DV tape in the Z1 there is no scaling taking place on the component outputs. Conversely, you can choose a menu option to scale HDV 1080i on playback down to SD resolution through the component outputs.