My 2004 E Class 50 APS CD version 2.1 is long in the tooth and unaware of many new roads, i.e. M6 Toll etc. I want to upgrade it with new CD's. I understand that the 2007 V5.0 is the latest, however I was quoted £229.00 from my dealer. Seems a lot for a couple of CD's. Does anyone know of other sources. It would appear that the E Class is out of step with all other models too and the CD's are bespoke to the model.