As most of you know I drive a '10 SHO, I've pondered exhaust, but I am not sure I want to do it or not. There is a myriad of options for the car:

1) Stainless cat-back system from flowmaster or corsa ~$1000
2) Put on some new Mufflers just to get a little more grunt under acceleration ~$350
3) Higher flow downpipes, which is the highest possible horsepower upgrade of any part of the exhaust system. ~$1100

or

Get an air intake to get more turbo noise so I'm happy with that for a while, I've read up on the things till I was blue in the face and still can't decide if I think they or good, bad or somewhere in between.

Another problem is, I haven't heard, in real life, an SHO with exhaust, so that aspect also scares me, I don't really know which component buys me which kind of noise.

How do you guys usually approach this quandry?