The NAS drives are basically lower-cost Enterprise drives. Like the Enterprise drives they are designed for 24/7 operation, have the proper time-limited error recovery (so as not to be dropped from an array) and are designed for higher vibration tolerances (multiple drives in an enclosure). In general from what I've seen by comparison the more expensive Enterprise drives are rated for 10x fewer nonrecoverable read errors and have a lower AFR (Annualized Failure Rate).
No offense, Scott, but would you actually recommend
a NAS drive from Seagate?