What banks are using ISO 20022?

I'm curious to know which banks are currently utilizing the ISO 20022 standard for their financial messaging. This international standard has been gaining traction in the industry for its enhanced security, efficiency, and flexibility. Are there any major banks in particular that have embraced ISO 20022, or is it a more widespread adoption? It would be interesting to understand the motivation behind their decision to switch to this standard, and how it's impacting their operations. Additionally, are there any challenges or obstacles that banks have faced in implementing ISO 20022, and how have they overcome them?