Before buying from any of these guys the obvious questions to ask them (once you've established they aren't just phishing your credit card number) are whether the software comes in the original sealed packages from Adobe, whether they guarantee on a money-back no questions asked basis that the serial number is genuine and unique and the Adobe website will accept product registration in the buyer's name, whether it is a version priced for educational institutions being marketed as regular commercial product (which is illegal), etc. There's no end to gimmicks so be very careful.