Y pipe otions

ste01

Hi: lots of talk on the pro's and con's of "Y" "H" and "X" pipes. So what's the pro's and con's of running a true dual set up from the cats back.

Here in the UK, am limited on what manufactured after market systems are available without importing, systems that are readily available here are Nismo S tune, Invidia Q300 and systems made by Janspeed, Cobra and Scorpion.

So was looking at going down the custom fit road but have not seen much info or remarks on true dual systems. Any help or comments on this type of set up would be a great help

Thanks guys