The old D still sounds a bit better - seems to have more natural reverb/echo but it's almost hard to tell the difference between the old D and the new one. The good news, is that the new one has some things about it that I like better which makes me pretty optimistic. For non-piano techs, voicing seems a bit unreal until you experience it first hand. There is a natural inclination when I hear a piano to think - "that's just how this piano sounds, and that's final".
The old D needed new hammers badly. They were completely worn out and flat at the top and no more room for reshaping hammers.
Interested to hear about the hammers? Are you going to replace them - with Steinways or, say, Ronsens?