just as several other said, companies would not freak out when they see that you have their music in a mission. Nor would they even find out if it did, but the point is that they would rather not spend 100 thousand dollars on a law-suit just to get their song out of your mission, it is simply not logical for the company to do this, they would lose more money than they would gain. Legally it is wrong to do that, morally, I see that music is extremely expensive nowadays, 30-40 dollars a cd is just criminal. If I buy one album, I don't have enough money to buy another for at least a month. For that price i say that we should be allowed to use it in the manner that some of us do.
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But I would say that the duplication of songs should not happen in these forums, or in any other part of this site.
I'm not willing to take that chance that OFPEC runs into any problems, it would be devastating :'(