Piece togethere the exhaust, you may have to do some custom work but in the long run it will be worth it. My old setup was bassaini headers with a modified bassani x to slip on the 3" collector, and a set of dr gas flow tubes into 3" dyno max ultraflo welded mufflers and dumps.
I found a deal on craigslist for a full bassai exhaust with headers all the way back to the tailpipes, and thats what im running now, the car sounds the same with the bassaini mufflers as it did with the ultraflows, except alot quiter inside with the tails on it.
The flowmaster kit is alright but its big money, and im not into chambered mufflers either.
Id suggest if you are going to buy a set of high end headers tho, look into accufab, the other brands charge a ton of money for a nice header that is built well but hangs really low to the ground. I dont understand how someone charges close to 1000 dollars for headers and then you put them on the car and have to worry about denting them up on bumps in the ground.