I believe Enterprise drives are more performance based then reliability based. The mechanics are still the same. Usually an enterprise application requires a fast drive, something like a 16MB cache and 15k RPMs is the norm, even if the drive is only 150GB, put those in RAID and you have a very fast access source for a large network.
There of course are slower, and larger backup drives, and tape backups as well... but again I can't imagine that they are any more reliable, if the two drives are comarable in other regards. SATA is Still SATA, though Fibre and SAS might be more reliable than SATA or PATA.