Hi Together,
I am currently preparing for the certificate and am using all possible sources available to me.
I have read the Learning Path and the Guide in English as well as in my native language.
The open assessments Scrum Open and Product Owner Open I pass quickly with always 100%, at least in the last 10 - 20 attempts.
I also prepare in parallel with the open assessments by Mikhail Lapshin, but I have to say that they unsettle me more than they help.
The following example: