S9 - Like EE9 mentioned, Jasma approved exhaust does not sound loud at all. The Silent Hi-Power is Jasma approved. Noise level - well, there is definately an increase in noise but on idle and low rev (normal drive), the sound is not loud at all. I did not decat, so I am not sure how it sounds if you decat. When you accelerate hard, the sound is noticeably loud, loud enough for me and for your neighbours to hear for sure.
However, the sound is supressed to a certain extent by the sound of the turbo spooling due to the aftermarket intake box. Regardless of what types of air filter you use, as long as it is open air (not in a box), the turbo spooling will be significantly louder and it will drown the exhaust sound a little, hearing it from the cabin.
Compared to ori, the car is definately much more powerful. Now, I can feel that the brakes are inadequate for the power. I was driving home one day and decided to do a little aspirated drive up the hill. I accelerated hard up the hill in 3rd and then 4th, maintain at 4th through a bend, dropped to 3rd as i approached a 160 degrees left uphill and brake, double clutch dropped into 2nd just before the turn... but the car couldn't slow down in time for the turn. Luckily the road also sweeps to the right, so, I decided to take the right sweeper rather than risk an understeer (thankfully though there was no car coming from the opposite direction). I don't think I was too fast going into the lefthander. The brakes caught me by surprise as I didn't know it was this inadequate!
Anyway, back to your question, the setting right now is not complete. The next on the list would be the brakes and the suspension. After this is done, I think I can drive the thing like a rally car (save for a LSD)... In my opinion, the brakes are a must!!! I personally think that the stock brakes are inadquate for even a stock std evo, let alone a slightly modded one. Just my opinion.... ok.. enuff of my nonsensical spill.. hope that answers your question though.