I have the EX2 . . . .it runs western digital’s OS3, similar to the Passport Wireless, and the now defunct “My Cloud Personal” line of products.
The “Home” devices are running new firmware written from the ground up. Most of the “tricks and features” on the NAS boxes and the “personal cloud” units simply do not apply to the home products. I don’t know much about the software on the Home devices. . . except that they are somewhat “dumbed down” to make them easier for noobs to use. A very, very fundamental difference is that they require an internet connection to function. I believe this is because user authentication is cloud based. . . .unlike anything running OS3.
So the software overall is much, much more limited on the Home Units. Not sure you can use SSH commands (Linux command prompt language); or file transfer protocols like FTP.
On the flip side; I believe (I do not know) that security is much improved over OS3. My understanding is that there were a few backdoors in the old software, and it was not that “tight”.
Overall; my impression I that the Home units are much, much, more limited in capability and most advanced users prefer the OS3 “personal cloud” units and the flexibility the software provides. Most people that I see posting in this forum that have units of each type really dislike the limitations of the Home line. I have looked at the box for the Home products: They sure read like a “NAS” unit. . .but most people who have it don’t consider it anywhere close to a true NAS device.
Regarding the EX2 itself. . . in addition to the software difference, it also has a much more powerful CPU (and more ram?) This allows the unit to be used as a media server within your home. Or even across the net. I routinely stream movies in my house to home theater systems (via a streaming stick) or to a tablet. I normally use either Twonky or Plex as the server software. The software resides on the NAS itself. (note: While Plex does work, the chip is still not powerful enough to do on the fly transcoding. You need something with a full blown intel chip, like the PR4100, if you movies are not in a format that can be used directly on your final device)
I don’t know about the home duo. . .but the EX2 does allow for hot swaps of hard drives.
So: Bottom line: My recommendation is to get the EX2 Ultra and don’t look back.