It really depends on what your purposes are with the car. If you are building it for yourself to enjoy and drive, then to me the tag does not matter, unless your goal is to build it back to original condition. If the original options that a car came with are important to you, then you need one with the tag, unless the car has the original Broadcast sheet, which will also give the options that were on it. In order to reproduce the Data Tag, you absolutely need the original Broadcast Sheet. As far as value, again that is up to you to decide. If you are looking to build and resell, then the missing tag could be a big deal. If you are looking to build to suit your desires, then to me missing or not does not matter. Hope this helps.