I do from time to time. European Professional Pilot Studies is perfect for it. All the relevant stuff needed to pass ATPL exams and review your general knowledge from time to time. It served me well to prepare for job interviews.
I do it because I find the content interesting an because in the near future I might become a TKI, but when I have my LPC/OPC I only study on my company manuals. ATPL general knowledge is not relevant for this scope.