The non-success story is an intriguing question.
The type had some success in its military declinations (0-2A) during the
Vietnam era. It is recognized and often used today as an engineering testbed
for a variety of new designs and improvements, yet in its principal designated
market it quickly developed an "ugly duckling" reputation which even today
leads to depressed prices.

There is not doubt it was noisy, inside and out. The high prop RPM and the fact
that one of them was close to the rear seats contributed to this. Also, several
models were anything but speed demons, giving lower TAS than some competing
twins. I have heard (don't know the veracity of this) that cooling on the rear
engine was inadequate, leading to a whole host of significant maintenance and
reliability issues.

We'll see how well Adam does with their new, spruced-up 337 (I know, I know -
this airplane bears no similarity whatsoever to the ugly old mixmaster - yeah,
yeah). For now, I see the 337 as one of the rare "deals" available on the
market, the price/performance ration being favorable,in addition to the
"safety" factor of a twin. Saftey is in quote here because most light twins are
more dangerous than singles in the event of an engine failure, so the safety of
a second engine is only theoretical - whereas in the case of the 337 it is
real and useful.

G Faris