The day finally arrive when my tech took the action out of my piano to replace the hammers. It has been a long wait. It took a while to make the decision to cut loose with the money ($1900) but I know the improvement will be transformational. The old hammers were like rocks and the sound was harshly bright. It did train me to play softly so it probably forced improvement in my technique but I'm also sure I lost some of my hearing over the last couple of years playing it. I think the family will appreciate it too. So, even though I'll be without a piano for two weeks I am jazzed.

Do they replace the whole hammer or just the felt that goes around the wooden part of the hammer? I ask because the refurbished U3 that I looked at supposedly had the hammers re-felted (is that a word? )

Hammers can be re-felted, but this is usually only done on vintage (historical) pianos where new parts matching old ones are not available. Normally, the whole hammer (felt and wooden core/molding) is replaced as a unit. Times 88 of course.