Emailed him. Still not sure if I want this setup or a small compressor but eh, we'll see what he has to say.
Derr, forgot to ask him, what's the difference between the Auto and the Construction/ATV models aside from $10? It looks to me like both ads are identical. 
I think the only difference is the hose, one has a straight hose, one has the curly one.. Be sure to ask which you are getting.
Blazer, I am not sure if you want one either. If you want it for trails, I would get set up with a tank to refill. In my case, I already had a tank to refill, as that is what I used in my full-size.. in my opinion, the Trackkicks are too small to have a 20# rolling around in the back.. I guess you could mount one..
I originally bought mine for my ATV, and had the 20# in my tow rig, so it was a natural to use it in my Tracker too.
To be honest, even if you don't use it for day to day trail rides, the kit is so handy to have around the house, you just won't believe it. Of course, I am the sort of person that is always working on something, I use it to blow up footballs/basketballs etc, bike tires for the neighborhood kids, ATV tires, 4x4 Tires, blowing out computers, using an impact where I can't get air, cut off tools, you name it.
I must admit, being able to fill it myself for less than a buck is what makes it so handy for me..