ECU Pro is just that, they are professional in every way. Before sending the unit I called with a couple (probably stupid) questions, they answered the phone and my questions; not common customer service these days. I packed and sent the parts they needed and received an email notification indicating they had recieved the equipment and laid out the next steps. In just a couple days I received an email confirming the repair was successful, with a video, and that it was being shipped back to me. After re-installing the parts, my '08 335i was back to running strong and smooth. Thank you!