Best for me? Stock cat-back with a cutout. Very,very quiet when you want and loud when you need it.

id probably be the same way if i was around obnoxiously loud cars year around like you. The Dual Dual does sounds nice.

I'd go for a Magnaflow and an e cutout. That way if its not loud enough for you you can just open the cutout. Or get a Borla and put a cutout in place of the plate like Joe said.

I do have to agree with don, I have a stock location muffler and it's quiet down low and sounds good up top, I think most people would be happy with the sound, then add cutout.

Here is my 236/240 cam with a magnaflow with E cutout. Cutout open the closed

http://youtu.be/6a-kCwmjEsY

That does sounds good. Still undecided. Haha.

Magnaflow sounds very good with LT's and ORY. I say Magnaflow, its a very good quality stainless system with easy install. I have that setup on my LT1 and its not too loud but its a screamer at wot for sure. Definitely gives a distinct sound for an LS car since most exhausts are raspy. However on my CME setup I think my setup is pretty restrictive from the axle back. I was thinking about getting an E cutout to put before but now that I see that GMMG thinking about that and selling the magna. Would you be interested in mine?

Also a word of advice for anyone doing header install. Do other mods your thinking about at the same time while the exhaust is out! I screwed up and didn't do my motor mounts during mine. I just did them last summer with the headers in the car and even on a lift it was terrible. Harder than dropping the trans and doing a converter + shift kit... So yeah do motor mounts, and any steering linkage maintenance, or anything else in that area. Gaskets or whatever.

and for motor mounts do energy suspension or some other brand of poly mounts. Do the engine and trans, you will feel a little bit more vibes but not bad. I have noticed some major harmonic vibrations since I did mine but I also put Joe's LS1 aluminum driveshaft in and think it might be out of balance. Like others said o2 extensions you can make some from junkyard connectors if your cheap like me or just buy some. Exhaust band clamps too because u bolts catch trash bags and crimp the pipe so it never comes off. Jegs' ebay store has the cheapest clamps I think.

Thanks for the info Klab. I think you guys finally persuaded me to go with magnaflow. It does sounds very good and can be quiet. How old is your magnaflow?

Pacesetter LT's, ORY here
I run a hooker CB, plenty quiet at low idle, smooth tone at cruise, and I still get surprised at WOT.

I hear good things about Magnaflow both in cost/sound.

if plugs are on your list get a good set of wires too.