Front isn't necessary if you aren't tracking, the guys getting fronts are actually trying to get more camber up front for the track.

The rears, I'm currently deciding between SPC and SPL, I've only been dropped a week and I'm waiting for my wheels/tires to be installed to do my alignment, so I've got a little time before I need the arms. But yes, Eibach's push rear camber to -2.5 or more, so they are a good idea

good to know have you noticed a huge change in ride comfort or stay about the same

pretty close to the same for comfort. Grip feels like it has increased, but that could be an effect of the rear camber :)

or lower center of gravity maybe ?

what did you set your camber 2

You should just spend $1k and get the bc coilovers. If you get springs you may end up with less wheel gap in the rear and more in the front.