Metal film is fine. On a SS set there is some risk going
with higher watt resistors. In some cases like the 330 ohm
on your 9-57 ( also on 9-90 ) board need to go from 1/2
up to 1w due to a near 100% failure rate. One place you
should never go up is low value resistors. They are often
used as a fuse only. Newer sets use a lot of them.
73 Zeno
