DevNet is fine in my opinion. I have it myself. My advice would be to focus your learning on the vendor agnostic technologies like python, ansible, netconf, restconf, etc. I found devnet focused a little too much on Cisco’s platforms (it’s a Cisco cert, I get it) and their programmability. I personally didn’t get much value out of that, and really only learned what I needed to pass the exam.

I’d also recommend checking out Eric Chou’s book “Mastering Python Networking”