Question About A Couple Low Minor Pitchers

I am wondering if you could give me your thoughts on the potential of these guys as well as there ETA. I have been looking at these guys this year and I am interested in your thoughts. Do any of them have
"Ace" potential?

Brandon Erbe
Deolis Guerra
Chuck Lofgren
Donald Veal
Franklin Morales (heard alot about him on here whats his upside?)