It is a league that is getting harder and harder to take seriously.
People with a gambling problem love it though.
They can't sell it as a minor league system because you know what the NFL minor league is called? The NCAA! They make a big deal about the players who get a shot at NFL training camps (even though most get cut), but if we're being honest, those players would've been invited anyway even without spring football.
The only player I can think of where it worked out as a second chance league is Younghoe Koo. Chargers make a scapegoat out of him and cut him during his rookie season, he plays a few games in the AAF, now he's a top kicker for the Falcons.