I went with ARH's, no real reason except that the tuner prefered them. I understand that they are all about the same, though LG's are supposed to deliver a little more torque. Either way I think you will be very happy with the improvement in performance. Good LuckI need help making a choice! Not sure who is better kooks or AR. Also catted vs. off-road.
Headers will add much more rasp and some more volume to whatever muffler setup you pick. Deleting cats will double the effect. Crossover pipe is supposed to smooth out the popping, though my '07 pops and snaps obscenely- like a GT racing car- even with my xpipe. I was shocked at first, but now I LOVE IT!!! I'll have to post an audio clip once I figure out how. Jeremy Formato said he thought it must be a s/w difference with the '07s. It's the only car I've heard sound like that!what should be the sound/loudness of catted long tube headers with a full exhaust?