I ordered this product on 5th of April and got in my hands on 8th of April. As soon as I turned it on, I received the kit kat update.
I am experiencing a strange problem with my head phones. Some wired noise is coming from the left side ear buds when I hear any video / music / speech.
When I checked in google, I came to know that many users of LG G2 users are experiencing this problem and they all started to experience this, after their kitkat upgrade.