Unless you're moving VERY large files, there should be no noticable performance gain upgrading from a SATA SSD to an NVMe. The primary cause of spinning hard disks being slow was now the throughput but the latency.
I also use SATA with almost everything. I use a single NVMe drive for a dedicated swap disk. I just recently upgraded my drive that stores my virtual machine images to a 2 TB SSD (also SATA) and there was a significant performance uplift, simply because there were more individual flash chips to parallelize the transfer.
You may actually experience a significant drop in performance if you happen to upgrade from a SATA SSD with DRAM cache to an NVMe SSD with no DRAM cache.
There is a lot of nuance that goes into these performance characteristics, such as number of flash chips (generally follow the size of the drive), the type of flash memory (SLC, MLC, QLC), whether there is a DRAM cache, etc.
For example, I bought a brand new modern 500GB Crucial P3 NVMe to test against a very old 128 and 256 GB Samsung NVMe. The Samsung blew the Crucial out of the water for sustained for the entire drive capacity writes because of the DRAM cache, while the Crucial started out fast but quickly dropped to very slow speeds, both as the SLC cache ran out and the drive began to fill.
In this case, I too wanted to see if modern DRAM-less drives had improved, but they're still garbage unless you're really pinching pennies or have very low performance requirements, such as a vintage machine. It's not much more expensive to get a drive with dedicated cache; in my case, I bought the Crucial P3 Plus.
All performance metrics for NVMe drives are based on the burst speed of an empty drive. This is very unrealistic, and this kind of performance can only be achieved under brief loads that occur only periodically, and only on the fastest compatible interface. When in doubt, run some benchmarks when you receive the disk-- on the WHOLE disk, not just a few gigabytes.
