AT-200 is a dedicated BMW DME ISN code reader and ECU programmer. CGDI BMW is an all-in-one machine with IMMO key programming DME ISN coding reading function, BMW coding programming function, BMW E, F, G series diagnostic function etc.
Look at the comparison table between CG At-200 and CGDI BMW:
CGDI BMW and CG AT200 can both read some ISN code from BMW DME incl. MSV80/MSD80/MSD85/N20/N46/N55 etc. AT-200 will read much more BMW ISN code than CGDI Prog.
CG AT200 paid service:
1). MSD80/D81/D85/D87/MSV90 Write ISN + MSV80 Read/Write Data
2) Mercedes SIM271 Read/Write Data
CGDI BMW paid service:
CAS3 key match
BMW Enable / Disable key
You can pay what you need as you like.