First, unless the BIOS notes say there's a BIOS or Drivers prerequisite then you can go from 'RV1' -> 'RV2'.
My advice in short, if you have no problems then my best advice is NOT to flash. But if you do then never do a flash from Windows and instead do it from the BIOS itself using a BIOS based Utility; more MOBO's are bricked (ruined) flashing through an OS.
Examples 'when to flash':
1. CPU requires newer BIOS version
2. Non-OS Instability
3. Peripherals e.g. 2TB HDD requires new BIOS.
4. Memory compatibility ; where current RAM is causing errors or stability.