We use both and I've seen WD last out longer.

I've used both as well and I would recommend WD.

I've only used WD and it's working great ^^

Both companies are very well respected , they both have high quality products and if they have similar or equal products then all comes down to price (at least that's what I used to do all the time).But recently there have complaints against Seagate drives of dodgy firmware, bricked drives, and massive data loss.
Moreover after Western Digital RE4-GP, the first Enterprise class drive with Dual-core, 64MB cache and intelligent spin-management technology why go for Seagate?

Regards

Aditya

We use Seagate Enterprise drives as well as Western Digital Velociraptors. Haven't had any serious issues with either.

wd is best for me i m usign from last 2 years with no bad sectors

I would go with seagate, longer warranty and have heard better reviews. Dont get me wrong though, WD is good too.