Having more of the same tablet wouldn't make any difference in the case of the OS being a problem.
When you did the reset, did you choose the option to save any of the data on it? If so, it wasn't a true "Hard Reset" and would run into problems. Not uncommon. The reason being, if there was something on the tablet that was a cause of the problems, nothing other than a full "Hard Reset" would ever remove it. I would suggest (even though I did see what you said above) to do a "Hard Reset" using the instructions I will include below.
If that doesn't resolve it, then there may well be a problem with devices storage, which is not something you could easily fix. If it is under warranty, then I would suggest contacting the manufacturer. If it isn't, then you may want to try a local tech, or just get a new device, depending on what is cheaper.
A side note, while one could suggest trying to root the device and then install the OS from some location online (you couldn't get it from the other tablets), I would never recommend that as there are way to many risks, one of which is bricking the device.
To "Hard Reset" the tablet...
1. Make sure that the tablet is actually powered off.
2. Remove your SD card, if there is one in the device.
3. Press the "Power" and the "Volume Up" buttons, together, until you see the start-up logo on the screen.
4. Once you can see the logo, release the buttons and allow the device to enter the "System Recovery Mode".
5. Next use "Volume Down" button to get to the "wipe data/factory reset" option.
6. When in recovery mode the "Volume Up" and "Volume Down" buttons are how to can navigate and highlight what option you need.
7. Once you have selected the "wipe data/factory reset", press the "Power" button to select that option.
8. On the following screen, repeatedly press the "Volume Down" button until the "Yes - delete all user data" option is what is selected.
9. Then press the "Power" button to hard reset the tablet.
10. If you took your SD card out in step 2, when the device is up and running again, reinsert the SD card.