I got my new hard drives in today, so I will be down for the day whilst i transfer data over and get them set up to replace my dying set.
The new drives are WD Purple Surveillance drives. They are designed to run 24/7/365, and are rated at a 180TB (written) per year standard. They (all 4 of them) are 3TB models.
These drives are VERY sturdy, and are built for surveillance systems, so they are meant to run and write all day long.
Prices on Newegg:
500GB models are $47.38 1TB models are $53.99 2TB models are $77.84 3TB models are $98.49 4TB models are $119.26 6TB models are $204.99 8TB models are $209.00 10TB models are $399.99