I have took over from my brother in law few days ago. I checked that it has "Unlock" Bootloader. I have asked my bro, he mentioned he did not do anything. Just he asked my help to upgrade to JB. So I helped him.

Which Custom Kernel is suitable for Stock Rom as i read few posts above that Stock Kernel has some issue ?

Well, base on xda, the best custom kernel that suit the stock ROM should be from iodak v06. Maybe brother waja can further comment since he's using it now.

BTW, can any O4X user comment on how's this camera quality? I search through the web and seems like this phone is suffering the auto focus problem in both photo and video capturing (read from review below :

http://www.trustedreviews.com/lg-optimus-4...-verdict_Page-2

Wonder is the custom kernel may help to solve this issue?

Just rooted and flashed Iodak Kernel V6..

From my experience using Stock Rom, Iodak v6 suits me well...Plus using Trickster Mod to undervolt...
Setting the Governor and Scheduler to your needs, mine is Sio+Interactive...

Custom kernel DOES NOT solve the camera issue...

Nice, download trickster mod from google play for more advanced options of that kernel

Guide me how undervolt because as Iodax v6 value for max and min are 1.6 ghz .. How to reduce the max to 1.2 and min 51ghz ...

Many apps can be used to control that...If youre not an advanced user, just use SetCPU apps from play store but its a paid apps just so you know...Once inside the apps, just use the slider to set your min/max CPU freq...

About the Trickster Mod, later on if i have free time i will explain it over....Rite now busy transporting to Revolt JB Rom...Hehe

Sure no problem..

Kindly if you can do it now, im able to guide through...As im also online to configure my rom...

About the camera quality, is it really that bad? Especially the auto focus issue?
I read on xda that the JB update should have improved it.

JB update V20x already improved the camera quality but not that much...
But i found that each time snapping picture with camera, using the HDR function will capture the best image

Auto focus issue? Mine is working fine

I find that phonearena did a comparison between O4X vs SGS3 :
http://www.phonearena.com/reviews/LG-Optim...I_id3060/page/3

If you look at the video comparison towards the end of the clip, you can see the O4X can't focus well on the S3 phone.

Cant help it, thats the weak point of LG product, its developers didnt concentrate much on that...I mean LG Dev...

But its not that bad...I like the HDR functions

Ai....that's why it's triggering my dilemma again of chosing between this or Sony xperia v since good camera is one of my main criteria too.

If you care about camera shot quality, O4X cant promise you a 100% quality shots, but it does give you performance...Sony phone, yes, the camera shot quality is amazing...I dare to say this as i am too from Sony Xperia Ion LT28h, camera is just amazing...Sharp and precise

Great to know that you are also a Sony xperia user before. Generally how you rate the camera quality between O4X vs Ion? I mean sure not on the pixel since it's 8 vs 13MB, but how about the response, focus, capturing time (will Ion may take longer time to do shooting in 13MB quality photo, especially in multi tasking mode) and the real image quality?

may i know how to flash the iodak v6? install in internal memory or flash through LG flash tools?

On the pixel count side, Ion win the fight for sure...Focusing will take much longer time especially in low light condition...Real image quality depends, on daylight/light source is maximum, you able to get a pretty decent and sharp picture, but low light is pretty hard to do that...

Focusing time is a bit longer but its worth a shot with what you get later on....

Thats a big no, you can flash it from recovery mode or flash using Fastboot command...
Still you need to be rooted and unlocked BL....

may i know where i can get screen protector for this phone around shah alam or subang?

DirectD store in subang also got....But quite expensive...Ive bought mine from mudah.com.my...RM12