I have come to believe that Ronsen hammers are among the best.  They
are made the traditional way.  Modern hammers are steam-hardened for
uniformity, ease of assembly in manufacturing, and immediate tonal
satisfaction.  However, they are too dense and only become harsher with
use.  Many technicians like such hammers because they don't have to
undertake much voicing of them, and can get a job out the door quickly.
Ronsen hammers are more of a happy medium in density, probably do not
require lacquering, and little needling, and don't become so harsh over
time.

Mark Ritzenhein