never from them but from www.getpinz.com and used a card with no prob.You should check your card and find out if you are protected or what recorse you have if you get ripped off ,most will not charge you if you do.
I went directly into my pharmacy and bought 50 pins and syringes no problem...I wouldn't give my card out for 2 reasons..I don't trust the guy on the other end and I don't want my better half to see what I'm doing....