Last time I weighed in on this topic I was almost rode out of town on a rail. So let me be careful.

I have done this sort of manipulation to recreate covers over the years likely as much as or more than most. My conconclusion is, if you need the chords - buy the sheetmusic, if you need the midi - purchase it from a professional (in fact HC provides recommendations for two sites and I fully concur). Anything else is just messin around - which maybe is what you want to do. But, nothing wrong with that.

Final Tour - Not with a Bang but with a wimper!