I play drums and bass equally, and i switch off upgrading my gear for both instruments. this time i bought a pack of zildjian a custom cymbals off musicansfriend (which pained me to do), and i paid $650 for it. Well i got the box at my house, opened it up and found that m.f. shipped me two of the sets. I checked my credit card, and i was only charged for one. so what do i do with this second set?