ssl4000, I'm only an end user like you, so I can't say whether your drive would be eligible for replacement under warranty. That said, ISTM that your drive's performance is very good, at least as far as the HD Tune benchmark goes, and there are no signs of bad or weak sectors. Even though attribute 0B is worrisome, it still has not reached the SMART threshold, so AFAICS there are no grounds for replacement on this basis.
Even if Seagate's Tech Support were to grant you an RMA, you would still need to consider what kind of drive you would get in return. It will most probably be refurbished, with an unknown fault history. It could also be that the replacement will be a Seagate rather than a Samsung, which may or may not be to your liking.
There is also the matter of the G-Sense Error Rate which suggests that there is something amiss in the drive's environment. This may affect the replacement drive in a similar manner, so if it were my drive, I would try to pin down the cause. To this end I would disable power management (including APM) so that any load/unload cycles would be due solely to shocks or vibrations.
Whatever you decide to do, ISTM that you should implement a robust backup strategy.
