I believe most of the negative things said have to do with the coupon printer software you must install.
The Coupon Printer allows us to offer you this coupon. You should know that:
It Is Anonymous
The Coupon Printer does not gather or ask for any personal information about you or your computer.
The Coupon Printer does not report any information about your Internet use. It is only used for coupon printing.
It Is Secure
The Coupon Printer is an industry-standard ActiveX control or Internet Plugin.
The Coupon Printer provides security features that are needed to provide you with a real coupon you can use in a store.
The Coupon Printer provides encryption to make sure that your privacy is protected.
It Is Trusted
The Coupon Printer is provided by Coupons, Inc., the industry leader in secure online coupon promotions.
Coupons, Inc. is our trusted partner, and provides services to many large companies.
Their EULA apparently states that the registry keys installed with the coupon printer will not be removed if you uninstall the coupon printer. Have a look here: Coupons.com and TRUSTe: Lots of Talk, Too Little Action
Quite frankly, I wanted a coupon once that required the installation of that "little piece of software". I said no thanks. A Guy