I have worked virtually all main and some of the lesser known
reproducing actions.  I believe if the quality of the build is
first thought about, they come in this order:

  Welte German T 100 and T 98
  Hupfeld Dea
  Phillips Duca
  Hupfeld Triphonola
  Duo-Art
  Ampico and Welte Licensee

For ease of restoration I think the list is very different, but I would
put the Duo-Art and Ampico at the top of the list, with the Welte
German instruments among the hardest to restore to a _high_ standard.
The quality of the recordings?  Well, that is a matter of personal taste
as well as there are good and bad rolls for every system.

I think the Duo-Art is probably the best for ease of serving up and
restoration; the rolls are very plentiful and they generally stay well
regulated just as does the Ampicos.

On the other hand, the early Weltes are beautifully crafted and fitted
into the creme de la creme of European pianos.  They do require
very careful restoration and adjustment and loving care.  We must
realise that they are nearly 100 years old and such technology was an
amazing breakthrough in the history of the reproduction of sound.  We
should always consider what they were competing with: the Gramophone
and phonograph and later the early crystal radio sets.

Therefore I believe if you are not a serious collector and technician go
for a Duo-Art or Ampico.  For the more serious collector try one or
more of the rare German systems.  I still believe the best Duo-Art you
can buy is a Steinway or Weber upright with the huge six-lobe triple
exhauster steamboat pump.

BUT, always remember the system will be only as good as the piano
itself.  The piano must be in tiptop condition before you even start to
regulate and adjust any reproducing piano.  If the piano is poor it
will not matter how much great restoration you do to the pneumatic
action; it will never live up to your expectations.

A personal point of view through my own personal experiences over the
last 27 years.

Jonathan Holmes