I was recently in the same situation. I wanted to buy a 1 TB external hard drive with FireWire 800. I already had (and still have) three Western Digital MyBook drives. They are all older models and have all been great since I got them. One is going on 4 years, one is 3 years old, and the last is 2 and a half years.
When I bought a new drive a couple of weeks ago, I looked into the matter and saw that the newer MyBook drives had gotten very poor reviews on the online Apple Store, so I decided to go with something else. I found that the LaCie d2 Quadra has been getting very good reviews and it is one of the top rated products on the online Apple Store, so I got that one.
It is nice with all its ports (2x FireWire 800, one USB 2.0, one eSATA, one FireWire 400), though I only use it with Time Machine on my MacBook Pro, so I really don't need anything else than FireWire 800.
This LaCie drive seems very good and it has a solid and appealing design. But if noise is of any concern to you, I would probably not recommend it, as the hard drive itself is quite loud. It has no fan, though, so you are not going to be bothered by that. But in use the drive itself is rather loud.
I think this drive is a safe bet. It has 3 years of warranty from LaCie.
I hope this was helpful.