I have two Seagate ST31500341AS 1500 G drives ( as indicated on the DNS 321 status page ). Other than the hung at 94% formatting issue they're working fine. I found they ran hotter than the two 1GB drives in my DNS-323 so I had to up the email temperature alert so my box wouldn't shut down when accessing the drives for an extended period of time. They run at 45C idle and about 50C running, I had to increase the temperature alert to 55C.