White adds 5bhp I heard.Just for looks
Apparently it depends where you position the strips - eg: if you put them on the side of your car, it improves the handling when going round corners.
If they are positioned on top (bonnet, roof) it increases your acceleration time.
They are the most common places. Who knows what will happen if you put them elsewhere!
I was told that adding strips is adding weight so your making the Bhp - power worse.