For what it's worth, ordering by credit card over internet from a "reputable supplier" (like on DD's list) is probably way safer than any other way to use a credit card. There are no slips of paper or carbons floating around. Most on-line suppliers use a third party to process transactions, so no one really even sees the credit card info. If the "third party" processor started ripping people off there would be bad things to happen to them by the credit card company, so they arn't a major concern.
On top of that, credit card compnaies limit your liablity anyway.
If it is a choice between an on-line order and calling them up and giving them your credit card number over the phone, the on-line method is probably safer.
Powder, Inc has worked for me in the past with no hastles. Order as much as you possibly can when you order it. If you can get to 25#, even with the hazmat fee you will be way less than retail prices. Powder, Inc will give you the "25#" price on everything as long as there are 25# in the box... it doesn't matter if there is 25# of only one grade. If you want to shoot blanks, you may want some 1F as well as the Cannon grade. Check out their "1F Skirmish Powder"... very economical.
One thing to be aware of... Goex prices are supposed to go up in February, another good reason stock up now.See the note about it on Powder, Ic's web site.