Should I roll back RST storage drivers to windows default AHCI if I have only 1 NVMe SSD drive in my system left?
What drivers are better (faster, less problems)
You can -- but you don't absolutely have to.
There is no material difference in operation (or performance) between the RST Storage driver and the Windows AHCI Storage driver.
There's a but (there's always a but) -- there have been some reports that some third-party SSD support apps (for example, that for firmware update) do not work through the RST Storage driver. This might represent a reason for removing Intel RST.