So embarrassingly I'm yet to replace the dodgy drive in my NAS; in getting onto it now, I came across the WD Purple range (supposedly designed for surveillance purposes), and a NAS-specific model from Seagate - both are cheaper than the WD Red I'd been planning on getting and come with the same three-year warranty. There also seems little substantial difference in noise or power consumption.

So my question is: would either of these other drives be an acceptable alternative to the WD Red, or should I stick to my original plans and get the Red?

Thanks for any advice.