Sorry guys but I have been using RC5 before it was officially released and have to disagree about it being laggy.
It's probably the kernel causing this if you didn't do a full wipe.
If it's an app issue where it FCs, then try uninstalling and reinstalling it.
I would highly recommend trying Abyss kernel. The latest one is a little buggy but 1.2 R1 works fantastic and I have been using it for a couple of weeks even with other roms.
You can download the kernel from here: http://db.tt/9plh7tJ1
Dorimanx is another one I would recommend as well.
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