KingRoot did root my LG Tribute (LS 660), but it also installed bloatware, an ad-serving and battery-draining charge screen. This adware gave absolutely no indication of a link to KingRoot, and I uninstalled numerous other apps before the attempted uninstall of KingRoot gave me definitive proof. The ad-serving charging screen came back, this time admitting the link to KingRoot. It also claimed it would let you disable it, but I had had enough by that point and it was a script from a zip file that installed SuperSU that vanquished KingRoot after a bit of a software tussle. The opened up memory space has been paying smooth dividends ever since, and the programs battling somehow felt like Arnold Schwarzenegger vs. Robert Patrick (who, by the way, I thought did an admirable job in "The X-Files" even as the show was crumbling around him), but that red light from the mechanical eyeball of KingRoot has finally been extinguished, and now I have a rooted phone. SuperSU from the start would've been much smoother.
one click root worked just fine for me a couple months ago http://forum.xda-developers.com/lg-g3/general/guide-root-lg-firmwares-kitkat-lollipop-t3056951