In the last 3 months I bought 3 Samsung F1 1TB drives.
First, in january I bought Samsung F1 1TB - great speed, no problems at all.
Two weeks ago I bought second one F1 1TB - strange sound after boot, speeds not so great (15MB lower than the first one in HD Tach).
Three days ago I received third one - no problems at all, speeds great (same as with the first one).
The difference? First and third have firmware ending with number 13, the second one (which is slower and makes strange sound after boot, but otherwise works normally) has firmware number ending with 18.
So, I am gonna keep using first and third one, and the second strange one will serve as a backup out of PC.
Just thought I would share my experience with 1TB drives : ).