I upgraded the original 4.1.2 to 4.2.2 about a month back. A few things came to notice in due course of time:-
  1. It runs sluggish at times
  2. The Battery is discharging much earlier.

I thought that maybe 4.4.4 will be a better option but seems there is no md5 file to be found. I have downloaded 3 rar files but found all to be having an image file!!

am usually good at tinkering with stuff but CWM etc seems a bit complicated.

I think will reinstall 4.1.2