You are a bit high especially for a Newbie and/or probably an alt. Going price for carded & hacked cards/reloads is around 20% from unknown sellers like you. Not a chance at 50% but good luck with your sale. How many minutes is your guarantee they won't get shut down?
I do not believe they have been obtained by carding or any illegal method. I've been in possession of the card for 3 weeks and it still works fine. So sir I'm not sure if your argument is valid here.