I'm using a combination of GC lists and these valueable checkers:
When playing around with the checkers finding an interesting one, which I currently don't fullfil, I put the challenge chache into a private Challenge List I need to recheck. The comment to this Cache is the Check Date and a backlink to the used checker. Challenges I directly fulfill come into my 'Finalisation' List same commented. This list goes on a regular basis into a PQ or can be handled through other project-gc capabilities. Writing 'fulfilled' notes into the Cache itself is not necessary and might confuse the Cache Owner .