Caronte

I'm considering replacing the DP along with the UP on my wrx 01 PPP. I want also to maintain a cat , so I thought about a sport cat. At the moment I had a conversation with PE who offers me an UP+twin dump DP + a mid section sport cat. They say this should prevent the Cel coming up. My concern is the excessive increase in noise. I know whatever dp i will fit the noise will increase, but which is the quiter one and to what extent the increase will be quantifiable?
Do you have any suggestion on other possible combinations of pipes?

Any advice would be greatly appreciated.

Thx Caronte