ASK NC

DS920+ with 4x WD 14TB Drives and 2x Samsung SSD 970 EVO Plus 500GB

Do these SSDs work well as cache drives?
How do you setup/initialize them?

Yes, Evo 970 is a good choice, they are on my recommendation list.Here is how to set it up.https://nascompares.com/answer/how-do-you-setup-initialize-cache-on-synology/I hope this helps.