I sent my ecm to PA by USPS 3 day priority mail, rom FL they rec'd it in 3 days over the weekend. They did not look at my ECM until Tuesday. They stated they got 50 ecm's in the mail on Monday. At that time I stated to replace it. It took ECUPRO until Thursday to ship out my ecm. They state on their website and the invoice it is Fedex 2 day Express. I did not get my ecm until late Tuesday, 6 days later. I took my car for a short ride on Wed. about 10 miles total, it seemed to work fine. The real proof will be tonight when I hve to drive 35 miles for groceries and back home. I am praying it does not stall, like it had been.