I would think the real controversey would be Armstrong vs. Kellogg. Kellog is by far not the runner that either Martinez or Armstrong is. But with an offensive line that is showing real push (plus or second offensive line downfield we have with our blocking receivers), I think Abdullah, Cross, and Newby can handle any and all of the running chores...
...which brings us to passing. Kellogg is a better passer. Better in the pocket, better in going through the reads, stronger arm, better touch, more accurate, and better at reading the defenses. As good as our running backs are this year, our receivers are an even more formidable weapon. If Kellog gives Enunwa, Bell, Turner, and some pretty good receivers behind them more opportunities for big plays, then I would go with Kellogg.
So to summarize: I would take a quarterback with 75% less running ability and has 25% more passing ability with the team we have right now...and I think Kellogg is less mistake prone than Armstrong or Martinez.