System 6 stays with me as much better, mainly because System 7 randomly crashed unless I had just the right set of extensions, while System 6 only went down for

System 6 stays with me as much better, mainly because System 7 randomly crashed unless I had just the right set of extensions, while System 6 only went down for me when an application (usually predictably) misbehaved. 7.5(.5) was truly terrible, though 7.6.1 ended up being remarkably stable.