I checked the link but couldn't figure out exactly what additional info the upgrade would add for the CX-9.
The ability to read some more data (including torque). But the one thing that will be very useful for us would be putting cumulative fuel economy as one of the 4 data points in gauge mode, rather than just instantaneous fuel economy. (that's one use of the new "add-a-gauge" feature). I definitely want the upgrade, and it doesn't get any cheaper than free, but I've been too lazy to send it back as of yet. I do wish it was user-upgradeable...