I just received my D801 back from LG repair after dead spots and phantom inputs on my device. LG replaced the touchscreen under warranty. Now the phone is smooth and very responsive, like it should be.
Since I had restored phone to the 10g firmware and unrooted before sending it in, I decided to flash the 20a KK update. Of course I lost root access and custom recovery, but I can live with that awhile I evaluate performance, which is, so far, better than 4.2 JB. T-Mo will eventually push the OTA update, which requires stock recovery. I figured I'd do it manually by flashing the .kdz file, which BTW does NOT wipe data. Despite large size (1.5 GB), file flashes quickly using LG Flash tool.
Maybe I'm just very happy to have my G2 back and working properly, but I like the KK update, although I hope a root exploit is found soon and we get a new custom recovery. That's why I donate to devs!
Don't know if that helps. Give KK a try, you'll like it!