seems like the sites have higher security, i think they got off a Fraud Score, i had a list of what they check for, eg; is ip backlisted, how close is it to cardholders location, timezone correct, is email a carders email, etc...i know some sites are very tricky, clean your java temp files too i know some cleaners dont do them.... lots of different reasons, check the cards with AVS Mismatch to make sure there is enough money on card?