Quote Originally Posted by Simon R Galley View Post
...no real life tests I have ever seen, and I have seen lots, could support RA-4 of any type being more stable...on display...
Even as long ago as it's publication date in 1992, Wilhelm's opus predicted a display life of 54.4 years for the then-current Fujicolor papers (with tungsten illumination when displayed behind glass) and 29 years for Cibachrome/Ilfochrome prints under the same conditions. See Tables 3.1a on page 131 and 3.2 on page 135 here

for details. I'm unaware that Ilfochrome changed after that time in any way that would improve its light-fading stability, while subsequent versions of the Fuji RA-4 paper showed even longer life expectancies in Wilhelm's display tests.

Quote Originally Posted by Simon R Galley View Post
...ILFOCHROME is no more, and I have no axe to grind as they say...
Nor do I. I've always felt that black and white is the highest form of photographic expression, so it's ongoing availability of HARMAN's products that's of greatest interest.