I know it's not the same, but a GSI complete Scorpion SS system from cat back went straight fit onto my astra, no mods needed at all 100% correct fitment for my 1.4 merit, with C14SE engine and auto box, so seems they may be all the same as said from cat back.
Exhaust is nice and quiet, but nice deep note only prob is eats every year a rear exhaust hanger rubber, but only a few quid, pita to do at side of road though!!
Mine is the single hanger type and the back box is HEAVY.
tabetha