From an admittedly hazy memory, I think the main difference between the two was the safety notches in the cylinders, but that could be wrong.
The Freedom Arms guns were the original mini-revolvers about 25+ years ago, Freedom hasn't made them for many years. I heard some details of an agreement between the two companies a LONG time ago, but can't recall exactly why Freedom dropped their line.
You may get an occasional lemon from NAA, but they're pretty good about fixing them. I had to have the hammer nose angle adjusted on one, no charge.
I carried another one as a shirtpocket gun for the last three or four years I was in uniform. I didn't have much faith in the .22 LR from a two-inch barrel, but had no concerns about the gun itself.
Parts would be hard to scrounge for the old Freedom mini-guns, if needed, and I don't know if they'll even service them any more.
I don't think there was much difference in quality between the two companies.
Denis