I think the Arizona Hotshots have a bit of an edge here, and should be able to cover the -3.5 or -4 spread.
Coaching
Dennis Erickson and Rick Neuheisel both have one veteran offensive assistant coach and both have a veteran defensive coordinator. Both were mediocre in their most recent stints as college head coaches. The remainder of their coaching staffs are relatively unaccomplished. Erickson is 10 years older and hasn't coached in 3 years but Neuheisel hasn't coached in 7 years.
Advantage - Neutral.
52 man rosters
Salt Lake has 23 players that have been in an NFL training camp and/or practice squad.
Salt Lake has 14 players that have been on an NFL 53 man roster and played in an NFL game.
Arizona has 30 players that have been in an NFL training camp and/or practice squad.
Arizon has 18 players that have been on an NFL 53 man roster and played in an NFL game.
I've noticed that the Arizona Hotshots have many more players with blue wikipedia links = some info on the player at certain positions than Salt Lake does. It is not that difficult to get a blue wikipedia link. Basically if you make a 53 man roster or have been to multiple NFL training camps you should have a link.
At offensive line, Salt Lake has one player with a blue link, and he has started a handful of games in the NFL. For the Arizona offensive line, they have one player who has started a few NFL games, another than made a 53 man roster and played in a few games, and two other players who were final roster cuts and bounced around the waiver wire.
This offensive line blue link disparity is similar to what I observed in the Atlanta vs Orlando game. Atlanta had one OL with a blue link, Orlando had five. I watched the entire game and Orlando's OL blocking was vastly superior to Atlanta both in run blocking and pass protection. I'd expect something similar in this game.
Salt Lake linebackers had one blue link, Arizona linebackers had seven.
Both teams won their only preseason games relatively easily. Salt Lake beat Memphis 29-15. Arizona beat Birmingham 36-17. Now these preseason games don't mean a whole lot because every player presumably gets playing time, but for some sort of comparative score, Birmingham just beat Memphis 26-0 in their week 1 game. It doesn't mean a whole lot but it's a tidbit.
Advantage - Arizona.
Arizona has homefield, shouldn't count for a whole lot since I don't expect Sun Devil Stadium to be too packed. Arizona has the Sun Devils and NBA MLB NHL and NFL franchises so they are not sports starved like some of these cities. Still not having to travel and stay in a hotel, etc should count for 3 points or so.
I don't see the huge talent and coaching disparity that I saw in the Atlanta vs Orlando game, but Arizona is the preseason favorite to win the AAF championship and they are at home:
Prediction - Arizona 23, Salt Lake 14.