4-bay low cost NAS comparison?

[Enquiries]

Hello.
First of all I want to tell that I appreciate your work here, I won't have found similar quality content in brazillian websites.
I am searching for a NAS and I found a WD My Cloud EX4100 for $ 400 equivalent price here. I also have found both Asustor AS3204T and AS3104T for the same price each one. The question is: The EX4100 is used and the seller gives 6 month warranty but the device appears to be better than Asustor ones, even they're brand new ones. Ignoring price and warranty time, I would like your oppinion about these NAS models, which one would you recommend in performance and reliability? Here in Brazil prices for NAS are too high and those ones are good opportunities for my budget.
Thank you in advance.

[ed]

Asustor is trying to make very innovative products and software, but reliability will not be as good as WD. AS3204T is a better spec model compared to WD EX and other Asustor. If you need a good NAS server and no other things like apps and other fancy things then WD is a good choice. But if you want a bit of everything- get AS3204T.I hope this helps.