The new pipes are 2.25" to match factory pipes. I honestly can't remember the name of the converters but really it doesn't matter because they don't replace any other factory catalytic. The whole idea is to replace the factory muffler with something that will give you free-flow and a better sound. I could of cut the factory tips off and welded them to the new pipes but I decided to preserve the factory pipe and muffler/tips (stored away)and I like the round, aggressive look.
The cost was equivalent to about $400. U.S. but the biggest part of that was the custom pipe work. The exhaust fellow worked on the system three separate times only because I didn't have the tips during my first visit and then after the second visit to weld tips on and try that set-up, I decided to add the free-flow converters to mellow the sound (3rd visit).
This cost me a little more money in labor than it could have if I knew exactly what the sound would be like beforehand.

It is difficult to describe affect it had on torque because no measurements were taken but I can say that I notice very little difference in bottom end performance but certainly the engine seems to open up more in the top end gears.

We have a very strict emissions test in Ontario that must be done every two years after the vehicle is two or more years old. I should not have any problem whatsoever because I have not touched factory converters, sensors and in fact if anything the vehicle should be more emissions free because of the additional converters. The muffler doesn't do anything but add a lot of weight and muffle sound.