I just installed them. They come with a nice gasket and I got the 1.5" primaries with the O2 sensor port. They seem pretty solid and really only save maybe a pound over stock. The collector exits about 3"-4" towards the center of the car and hangs down about an extra 1/2"-1". You have to install them but "feeding" them trough the under side of the car, unless you have the engine out. I bought some 1200F ceramic paint and coated them, but I only let it dry for about an hour, so when I fire the car up (very noisy, I need to sneak off to the muffler shop tomorrow) the paint bubbled pretty nastily. Ah - the sound of open headers... I can't wait until I'm finished with the rest of the exhaust. I have a racing muffler coming next week. Other than that, I'll stick with the hi-flow cat and 2.25" pipe.