Check out this thread in the S3 forums. You will learn more from this thread http://forum.xda-developers.com/show....php?t=1890708
about pros and con's of each, learn how to install properly with loca, and why you should use loca.
In my experience with trying both ways on my S3 I learned a lot.
First time without loca and had very little issues except screen touches not always working and having to hit the power button off and on for it to work. Then breaking it easily about 6 months or less again.
Second time I used local but I didn't cure it properly/enough and it leaked into the peripheral devices like camera and eventually motherboard died.
Replaced motherboard and glass again with loca and cured it with a ACTUAL UV light fixture and it still looks and works like new. I did not replace the camera from the first loca mishap as it is just a flashing/downloading/ emergency so are phone now.
So I do say Loca is the best method. Just take precaution and remove EVERYTHING so you are left with just the LCD and frame. Apply loca as in many videos available and the use a real UV light fixture. Do NOT rely on sunlight or weak UV lights to cure the loca completely. Good luck.
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