The down time is quite a bit different. When you ship your ECU you are without it for about 4 days. 2+ days of shipping each way, even when he turns it around same-day.

With the cables you don’t have to stop driving your car as long as you can orchestrate the hardware delete with the arrival of the cables. Cables arrive, do hardware, do remote tune same day, and ship the cables back. You aren’t dead in the water during the transit times.

Having said that, I would recommend shipping your ECU for the simple reason that Dmitriy archives your computer data. Should your computer ever fail for any reason, he can clone your backup onto a junkyard computer and save you a ton of money vs having it replaced by BMW.

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