It seems to me that some songs are more accurately and completely tabbed/charted than others. Not sure of the process. Presumably Ubi acquires the rights to a song and then perhaps a group of Ubi employed musicians tab/chart it. Not sure about that. Presumably the charting for songs can be revised through a patch if they are found to be deficient.
Anyway, are you satisfied with the charting? I find parts of songs under charted. They seem reasonably accurate, just a little incomplete.
What are your views? Are you generally happy with the charting or not? Do you find some songs a lot better or worse than others? What about the different arrangements?