catalytic converter

Yes, OEM parts are more $$$$$$$$$$$. That sounds like a little on the LOW side for OEM parts. But they are made for the car. You can always price out a muffler shop to get an Idea of what an aftermarket part installed is. OEM parts are made for the car and bolt up with no problems. Aftermarket is made to fit all kinds of different cars so its up to you. Both tend to work fine.

Yes, I just paid $700 to replace the converter, and the rear O2 sensor.