I have spent two days reading the forums and today I have to make the decision of what tool I need to order. My choices at this point is either the Kent-Moore J-42385-500 or Time-Sert J-42385-500. Our Matco Tool distributor says that Cadillac technicians recommend the Kent-Moore set over the Time-Sert set due to threads on the inserts. I have looked at them and I swear they both look like the identical tool with the identical threads. The price difference is the only difference I can see. Is there a difference?