I'm running the Cobb catless downpipe but most of your down pipes are so similar that you won't notice a difference except in quality. Megan makes alot of nice products but i'd look for a non-flexible up-pipe. I had mine on for about 2,500 miles and it actually developed a leak so i junked it. You can get a solid one for about $150 or so, i'm currently running the Perrin racing up pipe and havent had any issues.
I really dont think you should order from IIR i ordered like 600 dollars worth of parts and they just never shiped them and they would never call me back and im still fighting to get my money back but yes on the DP and i would go with the perrin i alos have one and its awesome much smaller then other upipes but flows the same