ok i'm having a new 2005 35-0 sonic built with 525hps.which system is quiter?i know when the exhaust is open it doesn't make a diffrence.so the question which one? pros and cons

The silent choice will be quieter. The reason is the exhaust with be coming out just below the water level.Also with the Silent choice some will still come out your tail pipes.The switchable mufflers have part of the assembly outside the trasnsom,and the silent choice is all inside.With your engines the silent choice is the best way to go. With high horsepower engines you have to go with the switchable type. Both systems have to be turned off when above 2500rpm's.Here's a pic of our switchable type on our 2005 386STS.I also posted a pic of our 2001 358 which had silent choice.

I have a 03 Sonic 358 w/525's I put silent choice on it . It works good around marinas
and when you want to quiet down . but this year I am adding corsa mufflers.
The boat off silent choice and cruising above 2500 tends to get load after a while.
I figure that if I run a poker run where it doesn't matter then I will just remove the mufflers .And if someone points a disable reading meter at me it should not be a problem. Which props did you put on the o5?

The one thing with the switchable exhaust everything is above the water line..

Roadrunner I have an 05 358 with twin HP 525"s and I put on Hydromotive P-5X 27P and she runs 82 MPH in flat fresh water.