I recently purchased a NAS with 4 hdd's.
While configuring the NAS i have the option to put the drives on stand-by after x minutes of no activity.

What is the best for the drives, to keep them running 24/7 or to put them in stand by every x minutes?
While stand-by sounds like the best option, i think spinning up the drive 5-10 times a day can't be good for a drive.

What are your opinions?

you dont need the drive spinning 24/7 that would cause a lot of issue and over heating.

i set my drives to spin down after 45 mins

been using the same drive now for over 3 years and still works fine.

make sure it keeps it cool all the time