This is the hard drive that I used for my PS3. It's SATA 3.0Gb/s but the PS3 only reads up to 1.5 so you'll be fine. This is the cheapest 320GB hard drive that I've found for a reasonable price. I haven't had any problems with it. It's relatively quiet and sometimes it's even more quiet than the Blu-ray drive. And make sure to back-up your data!!! I lost 50+ hours of RE5 because I didn't back it up! Just make sure you have a large external hard drive, flash drive, etc., and make sure to back up your game saves first. If your external storage device doesn't have enough room, make sure to delete any installed game data, not save data, from the PS3's hard drive so you have room to back up.
This is the exact same drive I bought a few weeks back, works like a charm.