bunch of posts about this already. youll get a lot of different opinions, but the general consensus is you want a midpipe, either an x, h, or just divorced duals, your choice of 2 mufflers (flowmasters, force pros, magnaflow seem to be the most popular), and have a shop fab you dual pipes to run out the back. 'best' sounding, cheapest, and probably the best gains. good luck.