Samsung makes great TV's, great monitors, & great cell phones. I've never been too hot on their hard drives however. And I've honestly just stayed away from their opticals, so I don't know about those. (you can't go wrong with Lite-On or Pioneer, even LG for opticals)
I'd buy either an Hitachi Deskstar or Western Digital Black Edition.
WD obviously has a great name, stands by their products and offers a 5 yr warranty on the BE & RE drives.
Hitachi drives seem to last forever. There's also some great free bootable DOS apps from Hitachi, like the Hitachi Feature Tool & Drive Fitness Test.
Feature Tool lets you change drive settings through software.
Enable or disable the read-ahead or write cache.
Change the predefined capacity of the drive.
- Used when BIOS limitation exists and the drive is not recognized.
Switch the Ultra DMA mode. Change advanced power mode.
- Switch between lowest and highest power consumption (maximum performance level).
Configure SATA interface.
- Adjust maximum speed and enable/disable spread spectrum clocking.
Drive Fitness test helps you determind if you have bad sectors on the drive and lets you map around them.
I'm running 4x 7200rpm Hitachi Deskstars in RAID 0 on one of my systems. These drives are used 24/7 and have been going strong for over 5 years. (I have them set to never shut down as well) I get 592MB/p/s in read data bursts, and a steady 375MB/p/s read speed with data blocks 2MBs or greater.
My experience with Samsung may have been unique, but I had bought a Spin Point a long time ago and had to return it to Samsung for repair 3 times within 4 months. By the 4th time, I took it outside and smashed it with a hammer. Compared to what I originally paid for the drive, my return shipping charges could have bought a new drive.