I think you are safe. I am also getting the hafc kit soon but my customer service rep in the area said they aren't ready to ship for another couple of weeks. I never paid for anything yet though. I also talked to the mechanic in the area and i am sure this is legit. I just can't wait any longer. Keep us posted. by the way, who are you buying the kit from?
I spoke for an hour with the mechanic who is currently attending their HAFC training class. He was a nice guy, and quite knowledgeable. He says their Pre Ignition Catalytic converter was also mentioned at the training, but not in much depth because it's not available for a year. This is the only kit I've found that isn't just made in some guys basement. They have a 40'x80' shop, an actual CNC lathe and CNC mill. A lot of their stuff is made right there in house.
I've got a few friends who are interested in buying this kit if mine works out alright, which I am certain it will. THe owner of the company has a HOnda civic getting 85mpg with this...
I think that the key is the electronics. Other kits only include the hydrogen booster, but that isn't enough. YOu need the electronics to go with it to get the true benefits.
I recently attended and was certified as an installer for the HAFC. Located in South Central ND I'm quite a ways from you phantomcow but part of my install team was Papo from http://www.paposauto.com/default.htm
Looks like he's about 335 miles from Watertown but he's got quite a nice shop and is top notch mechanic.