I clean flashed .107 (Customized EU) on my J9110. Worked very well for the first few hours, then started lagging like crazy. Half the apps wouldn't open and would just freeze or crash on their splash screen.
Camera viewfinder would stay black for like 20 seconds before loading and then stuttering while trying to record a video or take a picture.
It got worse as time passed, I wasn't even home and it was borderline unusable because it would freeze when answering calls as well.
Very unusual behaviour.
The only good thing I can report about .107 was that the fingerprint scanner performance was much better than previous builds.
Flashed back to .49 for now and all is well.
One thing to note was that no matter how many times I redownloaded it, I was unable to flash .107 with NewFlasher, it would display a signature verification failure error when flashing one of the 'OEM' files.
Compiled the downloaded .107 ROM into an FTF and I flashed it with Flashtool instead and I had no errors. I wonder if that had something to do with the problems I faced.