Have used them twice. Both times the tow driver claimed that the cat converters were not original and knocked the offer down significantly.
The first time it happened I didn't think it was right but wasn't 100% sure so I let it go. The second time felt scammy and I was sure it wasn't correct. I sold it to him anyway but complained to Peddle about it.
To Peddle's credit, they made it right and reimbursed me for the difference between original offer and settled amount.... For both cars.
Tl/Dr - don't be surprised if the tow driver knocks the offer down but you can work with peddle on it.