There is a nice way to get a cheap good machine but requires lots of investigation and research.
This is to get a Teclast clone. Checking properly offers and carefully comparing Teclast C260 for instance with others you can get a Teclast clone.
Teclast is constantly delivering good firmwares for RK2608A rockchip devices adding new functionalities, which is what a rockchip owner needs.
Also has a fansite that will help you to know about your device,
www.teclasters.com.
Of course nor
www.teclasters.com nor
www.meizume.com fansites will help like
www.mympxplayer.org does, but are enough good to feel safe with the devices you'll get.
I was lucky to get a Teclast clone but my first choice will always be Meizu machines
