Dude I would insist that you return the 5 x 100 Vanilla GCs and ask your friend to give you back $500 in cash. Why the hell would he waste more money buying 5 x $100 Vanilla MCGCs and pay the $4.95 fee per card for an extra $25 in total? Why should your friend make your life difficult and make you jump hoops to get your $500 back OR make your friend find a way to exchange the Vanilla MCGCs into $500 cash. Even if you were buying WM MO's with Vanilla MCGCs you lose out on paying $1.76 to buy 2 MOs since you could only do 4 swipes per transaction.