[Q] Do any TouchWiz ROMs (i.e. FireKat) really speed up the phone? topic

I have a new T-Mobile Note 4 (that I'm using on AT&T) and the phone is quite fast, but I enjoy tweaking and am planning to root the phone for Xposed and a few other things, so I was also thinking about flashing a new ROM.

I also use GearVR so I need a compatible (TouchWiz?) ROM and was thinking about FireKat.

Does it really make that big of a difference?

I'm more concerned about performance than battery life, but of course battery life is important too.