I've had 1 Seagate drive go bad, and it did so with a SMART error about a week after I bought it. I took it to the Seagate service center, and they replaced it instantly.
-1 for having a drive go bad, +1 for replacing it = 0 for me ;p.
You are lucky you have a Seagate Service center local enough to take anything to. The entire process of mailing in a warranty on things is so frustrating, I give up. Half the time they send back a refurb unit that has its own problems (at least with other things), so I usually just trash it [anything, e.g. my Nikon glasses lenses that developed an interior crack in 6 months]. Example: Samsung cell phone. Sent it in for replacement. Got back a unit even more defective with a scratch on the camera lens (thanks Samsung). I gave up at that time. Typical of my 'warranty' experiences.
It seems experiences vary. I should note that I've pretty much stuck the last few years to WD's cheap 'Green' line of drives. Perhaps the specific models involved make a difference, perhaps it is just luck. I don't know.
As for that WD model (the WD20EARS and WD20EARX), they provide good speed, good power savings, and are quiet as I've ever heard a 3.5" HDD be. Oh, and they are half the price ;p.
For 2.5" USB powered external drives I've always went with WD too, never had a failure - and have heard people whining about Seagate's, but never WDs.
Sadly, in benchmarks I saw at a site somewhere, the latest model of the WD MyPassport SE 1TB is not as fast as the Seagate FreeAgent UltraPortable 1.0TB (both USB 3.0), but the speed difference is negligible for me. Who knows how reliable that site was though. Since this is my backup drive, I prefer going with who I trust. I am not sure about the 1.5TB model of the Seagate FreeAgent UltraPortable, which holds the crown as the largest 2.5" self-powered HDD made to date.
These 2.5" models i mention are the ones that shot up in price a few days ago. What?!? Did I buy a few WD MyPassport SE 1TB's before they went up? Oh, yea, that's right, I did ;p. I saw (and mentioned here) these prices were not affected, so took action. It was a bet that paid off, for once. Probably end up making a whopping $50 (total of multiple sales) after eBay seller fees and taxes, but it gets me out of the house (to the post office ;p).
Example: Pre-HDD 'shortage' I bought WD MyPassport 1TB for $79 on sale. Normal price was $99 though. When all this happened they stayed at $99 for a month or so (with cheaper deals here and there, got one for $91), so I bought a few. Now they are $169-$199. Sadly, I didn't notice until one suddenly sold for $119 via Buy Now (I was about to give up), and I was like 'WTF?!?'. Then saw the prices changed, came and posted here.