OBD Eleven gives dealer level diagnostics for VAG group cars. As an early adopter my c.€30 dongle came with lifetime "pro" access. They have since developed a subscription system. I believe they now also cover BMW, same dongle but additional/alternative subscription required. However, apart from being able to access and play around with settings and such like it's only been of real benefit on a few occasions, all in respect of Mrs. Catcher's old Fabia for which it identified a faulty sensor I probably couldn't have otherwise diagnosed and, on another occasion, told me which cylinder was misfiring when a new coil was needed. Obviously the latter would have been easy enough to diagnose without the same by simply turning the key with each cylinder disconnected in sequence, being a 3 cylinder engine it wouldn't have started at all with either of the good two disconnected whereas it would continue to start and misfire with the bad one disconnected.
