Everyone keeps saying their moto HD and HTC has it figured out and the HTC one, S3 and Note 2 have no lag compared to the S4... Neither one has 4.2 running on it. I have had 3 devices running 4.2 and a note 2 on aosp 4.2, none have run as smooth as a phone running on 4.1. I have always felt 4.2 as being buggy and laggy compared to 4.1. I would like to see if the other phones ran as well on 4.2 with their ui running on it.
Something to think about, the S3, S4 and Note 2 run basically the same UI but only the S4 running the 4.2 OS.
Each to their own, but this is my 2?.