Google engine failures on Nissan 2.5L motors due to catalytic converter fragments getting sucked in and destroying piston rings and scoring cylinders. It happened to 2 of my kids’ cars. I do believe the phenomenon requires the cats or precats to be very physically close to the motor, which is the case in this particular Nissan motor.There is currently a new # 2 engine
Regarding "drawback some of the dust into cylinders and cause wear on the cylinder walls."
Are you sure?
I know the engine is pushing out and not sucking from the catalytic