My Cloud Mirror Gen2 vs EX2 Ultra

I bought a 4TB My Cloud Mirror Gen2 and really like it. It is a little slow sometimes, but other than that it is fine. I primarily use it as a local media server (inside my network) using Plex Media Server. Of course, I am running out of space. I am trying to decide between the 8TB My Cloud Mirror and the 8TB EX2 Ultra. The EX2 has twice the amount of RAM (1TB vs 512GB), but a lesser processor (A370 1.2GHz vs an A385 1.3GHz). I hate to step down on the processor, but think twice the RAM may help my slowness issues. Any thoughts out there??

The WD My Cloud EX2 Ultra is the overall better NAS with expanded business-oriented features, performance and apps.