About 15 years ago a friend was cleaning out his darkroom on his wife's instructions and gave me things including many bottles of liquid Microdol which he had since his college days.
Last week I opened a bottle and poured out a small amount. There was no discoloration so I stuck in a piece of film. It shortly turned black. So I loaded up a roll of TX that expired in 93 and took a few frames through the window.
I diluted the Microdol 1:3 and developed for 17 mins. The frames looked pretty good all things considered.
I've also seen it suggested that Perceptol and Microdol are the same but the packages of Perceptol I just bought have warnings re some organic chemicals with strange names, so it doesnt seem to be the same
Mark