I've seen S&S headers, yeah there nice, but TOGs are better than them no doubt. TOGs were #1 and they may still be. I have no experiance with the ZZPs, but if there supposedly better, than TOGs are #2 without a doubt.
TOGs were the easiest header I've ever installed on a car (granted, i've only done RWD versions previously).
So let me fix that...
ZZP > TOGs > S&S > SLP > Pacesetters > the rest..