It should't be any more of an upgrade than adapting a 9 pin serial to a USB. You just convert it in the ECU instead of letting the adapter cord do it. The issue comes about that sometimes the USB adapter doesn't work well on some computers. I'm not sure of the details, but I know some people have had no problems, and some have had many problems, using a USB adapter. So hence the USB upgrade may also be just as unpredictable.