You are right but the guy you replied highlight a strong point, we want to write once very quickly just to archive something and chance of reading those is low.

You are right but the guy you replied highlight a strong point, we want to write once very quickly just to archive something and chance of reading those is low. But we would need to write it. (He did it every night. I just archive it and recycle the storage in my NAS, but not as frequent as every night.). If I want archive reading in the very long term, should use tape or as you say WORM. But not for hard disk usage. Low cost write quickly. That is the 5400 coming in but not this. But the key is to tell us so we can choose. Not as scandal like to get such knowledge and still hiding.