Root Sky Devices 5.0L "Elite" (with Android Lollipop 5.1)

I have just bought a Sky Devices "Elite" 5.0L (with Android Lollipop 5.1 stock firmware). I need to root it, in order to appropriately use Link2SD and remove a few pieces of software that came preinstalled. I have tried KingoRoot v4.9.5 (and some others) with no success: phone can't be root, yet.
Has anyone had success in rooting this model?

Thank you very much in advance!
Gabriel, from Buenos Aires, Argentina