Originally Posted by Laguna Seca Blue
It's interesting that you refer to it as the BMS flash conveniently leaving out the fact that you have to pay for a $800 Cobb AP in order to flash your DME.
Also, as Spool Twice mentioned, you can only set it and forget it if you have a steady supply of E85, if your fuel mix changes dramatically, well, you better be monitoring your data logs pretty carefully.
The file loaded to the DME is a flash map BMS has developed for use with the JB4 G5 ISO system. Right now the AP is the only platform that allows at home flash mapping so that is what they use to load it. Maybe some day some other cheaper option will exist. But for now that is all that is out to load those flash maps at home so that is why they support it. The AP device isn't very cheap but on the other hand it has a very good resale value so down the road when you turn the lease back in, etc, it's easy to resell it. All considered I think it's much better than shipping around DMEs, having down time, risking them getting damaged or lost, and not being able to have easy flash updates when new tables and tricks are added to the mix. You probably lose more in postage on your DME and a few days of car rental than the AP costs considering it's resale value.