I don't run into many who do COD, but if I do have that option, I use it. That takes away any worry of whatever you've ordered ultimately not showing up after payment. However, as someone stated above, I think it is also wise to keep one credit card only for OP use. I keep one of those "pre-loaded" ones for OPs - with enough in there to place an order but not enough for a double-charge. (There have been many, many cases of OPs double-charging). Sure, you can do a chargeback fairly easily on your regular cc, but why even put that possibility in the equation? We have enough stress as it is.