From a computer scientist:
Any claim that extra software is required to print coupons is absolutely bogus. It uses your own printer software after you install this program! In other words, this program does NOTHING in terms of making valid coupons. Why don't they just have a picture file for you to print? This is because this is not all the program does, despite what the site says.
It's an "exe" that installs an addon to your browser. Why is there this extra step? Why does it need access to Windows installation files to install an addon? This is so they can install more than you realize... They have unmentioned monitoring software embedded into the program.
Yes, you will eventually get the coupon, but you are risking your computer's data safety in doing so.