Might be useful in the car but I have a small portable for that already. So does my "Girlfriend" for her car (Well she's as close as I'm getting here, we are breaking up at the end of the month, which was our aggreement on day one, When the new motor goes in,, By By Honey).
I looked up the specs on the hand-held first linked in this thread. It delivers 1/4 cm^3 and I'll bet that isn't at 200 psi. A user can do his own math on how much space needs to be recovered in a tire that is 5 lb low but the bottom line is that the hand-held will be spinning for a very long time to get the air pressure in the tire up 5 lbs.