Mirror NVME vs Raid10 SSDs?

Hello, just started building my TrueNAS server it will have 8 spinning disk in a raidz2. I want that to be my main storage for plex media. I want to have faster storage for everything else (family photos/videos, documents, etc). I also want to buy a Flex 10 GbE for the TrueNAS, TrueNAS backup, and my computer. My question is do I go with four 2TB SSDs in a raid10 or two 4TB NVME drives in a mirror? If the is a waste do I save some more and do four 4TB NVMEs in a raid10?

You will get the best performance with raid10. That said though, if you start out with NVME and want to expand your pool you will end up with raid10 anyway.

Depends on the cost you want upfront. I’ll also note that you shouldn’t use normal off the shelf NVME or SSD’s. You might want to consider higher endurance SSD’s for your pool depending on your workload. Not sure what your budget looks like.