Hardware Policies - which is the better choice

I use my external HDD mainly for saving System Images and other types of backups. Attached is the image of the window of this Disk Properties>Hardware>Properties>Policies. Which of the 2 choices do you recommend?

 

I myself go with 'optimize for performance'. Too simple to 'click' on the 'Safely remove hardware' arrow.

 

me two, I always optimize for performance as this lets me format in ntfs also,

 

I also would like to select 'optimize for performance' but when I do, it is very hard to stop the drive and eject, to unplug it. Almost always I get the message to 'try later because the drive cannot be stopped'. This goes on for hours, and I am reluctant to leave the HDD connected when I am not using it because it has all my backups. I am worried about corrupting or garbling my backups inadvertently. I will certainly choose 'optimize for performance' if there is some way to unplug the drive when I am no longer using it.

 

when I get that message is only after I have moved/copied a large mass of data, to clear one that does not want to be cleared after a couple of hours, I just shut down, remove the drive and start up again. it is 50/50 really, I mostly use it so I can format in ntfs.

 

My Drive is already formatted NTFS and I don't see the need to do it again. If I do it, all data will be lost anyway. So I am unable to understand why you have to be able to format your drive from time to time. I just like to know

How does 'write caching' improve the performance of my disk? The speed of copying, reliability or what other benefit?

 

write cache seems to make the ability to eject the drive easier sometimes, other than that for all my research I cannot figure out if it is good or bad.

I do wipe my data drives every now and then and replace the data.