I cant correct any misinfo since I'm not entirely sure about the exhaust since I've never done the vert subframe swap. Just from what others have said, lol.. I guess its all heresay...
Its def lighter and looks better though
As for the part number, the receipt I have is in Japanese. A few years ago you could get them from any importer, but I just looked and dont see any on google, etc... I know it was a limited production part. Each one is numbered individual (as are many MS parts).. glad i picked it up when I did, lol.