I bought one Rhino box from a thrift store interested on the hardware and how hackable it is because is quite powerful, an RK3288 quad core 2GB ram 1GB ethernet and several USBs although all 2.0 unfortunately, but the major flaw in my opinion is the software. Android 4.4...
I started researching for similar boxes to try to reuse the software and lucky I discovered this box is a clone of Ugoos UT3S (https://ugoos.net/ugoos-ut3s-16gb-rk3288)
They have available several flavours of android and a dual boot image. I tested and it's quite nice. (Dualboot firmware: Xubuntu 15.04/Android 4.4 firmware v.0.3.1 for UT3S)
I ended up installing the (Android 7.1.2 firmware V4.0.0 BETA for Ugoos UT3/UT3s/UM3) NOUGAT and works surprisingly well. no issues so far.
For those interested in the piracy available back in a day in the original Rhino box image, in this image don't have it pre-installed. So you need to go down that road by yourself...
Have fun and keep hacking!