Passed yesterday, excited to do it on the first attempt. Definitely not an exam to underestimate. After reading all of the posts on this sub about the difficulty of the 210-260 exam I ramped up my studies and use of different materials.
What I used:
Boson ExSim - This is essential, they do a great job of preparing you for the exam material. The included whitepapers are a must read if you want to really understand the material
31 Days to CCNA Security - Actually a really good resource for filling in the gaps
OCG - Falls short on some material, but seems to hit other areas, Boson references it in several questions
CBT Nuggets CCNA/CCNP Sec videos - Great for filing areas you don't understand
Chris Bryant's CCNA Security Udemy course
VIRL for ASA/ASDM labbing
On to the next cert, thinking of starting the journey towards a CCIE R&S. What is everyone else working on?