I've had pretty good luck with Boeshield.
My commuter is set up as a 1x9.
I'm not very careful about drive train cleaning, I ride on all sorts of gritty/dirt roads, sand, mud, wet, ice, snow slush, etc. so I get more chain wear/stretch [this is also a possible downside to the 1x9]. A chain would last about 1000-1200 km. Since I started utilizing the Boeshield I get 1500 or so km per chain, shifting is smoother/quieter and no surface rust. Someday I'm going to try a "stainless chain", but they are $$$.