[Spridgets] Iridium Plug Question

[Larry Daniels]

What do y'all think of Iridium spark plugs?  My brother asked me about them
for his airplane.

He says he is happy with the mileage -- about 30 mpg at a slow cruise speed of
140 mph.  The motor starts before the second prop blade passes, so starting is
very good as well.

He has a flat six motor with a second, redundant ignition system.  So, 12
plugs at $7.40 ea. and he changes them every 100 hours.  It gets costly.  Are
iridium plugs worth the extra cash?

Thx.

LAD