I am currently using Meticulus's BeanStalk ROM which is based on Cyanogenmod.
It is quite quick, and it has a lot of features for customization.
Coming from a Pre KitKat ROM
Do a back up!
Do factory reset/ wipe (incl. /system)
In recovery: flash ROM zip file. (You WILL get an assert error!)
Read the warning on the screen.
Flash the ROM again!
Please keep in mind that your device needs to be rooted with a custom recovery in order for this method to work.