If anyone is suffering from equipment failure all the time with their servers, the perhaps like Davo had mentioned, it may be some external causes that is causing your station to die frequently. If you do not fix your environment, then you will not be able to operate trouble free.
The problem I see with people who has a NAS is they treat it as a computer piece. It is not. Like any server, a NAS is required to be on almost all the time which means it needs better airflow than usual, especially for those models that use forced convection. Another problem with NAS is that when it is on all the time, it needs clean power. Would you put "dirty"gas into your nice Mercedes Benz(edited by admin)? These are simple questions, and yet people with NAS either buy a surge protector hoping it protects it. What good is a surge protector when studies had shown that in North American, the wall outlet power is unclean! I also see people being cheap and bought a cheap UPS that somehow provides clean power. Some UPS models are designed to provide noise supression which is good for audio/video equipment but do nothing for your server. You need AVR (Auto Voltage Regulation) that provide smooth sine wave output to protect you from brownouts. Not all UPS/AVR capable towers do this and are built the same either. Some people cheap out and bought a $30 APC UPS block thinking that's good enough. Guess what, do you think a $30 device can protect your precious data? If you buy a $30 or even a $100 UPS/AVR, you simply treat your data as being worth $100. So don't go blaming people around saying that it's not my fault for the system to fail. Buffalo, Netgear, Synology, Cisco, Dlink, etc are have their share of problematic users when it comes to drive failures and power supply failures, both can be attributed to power irregularities.
If you are facing this issue, then perhaps it's time for you to buy a good UPS system. The mid-end to high-end of the Tripp Lite and APC both make good UPS/AVR. If you value your data, pay more. In the UPS/AVR, you will always get what you paid for.