I have a Giotto Rocket Blower too, but decided to go with the whole $130 package. I'd like to keep the Rocket Blower in my camera bag for blowing dust off lenses when the field. I will keep the FireFly at home for its designed uses on the sensor and camera chamber. If I am going on an extended shoot, I will take the FireFly with me, but I will not carry it around in the field.
Considering the amount of money I have spent on camera equipment, the $30 savings was not that important. Plus I like doing my part to stimulate the economy.