Well you have to remember that System 8 and 8.1 as we know them were never actually "meant" to be commercial products. They were cobbled together from this and that feature of the Copland project, and that in haste, so much so that it's kind of astonishing that they work at all.
The later 8.6 is obviously in much the same boat, but is extremely stable, which is a bonus, but its real assets are that it is much more complete than 8.1, and yet takes up so much less memory than 9.1, and is so much more nimble on machines that tend to choke under 9.1. MacOS 8.5 I just avoid as an unstable approximation to 8.6.
I have run 8.6 for these reasons on my 2400c, on a 6400, 6500 and so on. It can function well on about 96MB of RAM and yet it can run more or less all period software (occasionally with small hacks, as in the case of iTunes).
The later 8.6 is obviously in much the same boat, but is extremely stable, which is a bonus, but its real assets are that it is much more complete than 8.1, and yet takes up so much less memory than 9.1, and is so much more nimble on machines that tend to choke under 9.1. MacOS 8.5 I just avoid as an unstable approximation to 8.6.
I have run 8.6 for these reasons on my 2400c, on a 6400, 6500 and so on. It can function well on about 96MB of RAM and yet it can run more or less all period software (occasionally with small hacks, as in the case of iTunes).