Tronsmart just release the stock firmware for their vega s89 and vega s89 elite quad core tv box.
Vega S89 series are not base on rockchip anymore, they use the amlogic s802 chip. so the firmware and firmware update instruction should be different with the rockchip ones.
The stock firmware is Android 4.4 Kitkat. with XBMC , Google Play Store built-in.
also it give you different screen resolution choice, from 720p to 1080p, even 4K.
so here we go:
Here is the instruction for how to install the firmware:
Get the original tronsmart vega s89 here: