CBM - Engine Check Codes

Folks,

Who has used the system to bring in Engine Check Codes to the CBM module? If so, have you tended to cherry pick the most critical codes. I'm thinking that a lot of them are industry standard, eg: P0601.

Any feedback would be appreciated. Client has kicked around using CBM to record Engine check codes but not sure yet what the ROI is. eg: How often are these codes changed by the industry? does, for example, the P0601 only apply to certain model years and later years have a different code to cover ECM checksum errors. If it's a moving target then I don't think there will be much take up on it.