I searched for the forums for existing threads but they seem outdated.
So COBIT 5 for those not familiar with it, is an IT governance framework. I didn't find any cert that focuses on IT Governance except COBIT 5. 
ISACA offers a free study guide for COBIT 5, but I couldn't find any practice exams. I'm thinking of reading up those frameworks PDFs and have a go at the exam
Q) Why do I need it?
A) I don't need it, but I've been doing lots of IT governance work, and NIST work...and found the concepts to be straightforward to me after a long technical career. I see values in those frameworks and I'd like to formally learn a bit more. I got to implement those frameworks and see what they look like in the real world so my experience isn't just governance on paper, so I figured why not
Are there worthwhile practice exams out there? 
Do YOU have any experience with COBIT 5 ?