MIA is good for the outbound, as others have said. However, ground traffic at MIA can get very squirrelly and long delays waiting for gates are not uncommon. Make sure to book a well-padded connection (anything below one hour is self-sabotage IMHO). Worst comes to worst, he can spend extra time in the terminal or, if eligible, the lounge.

DFW is borderline for the outbound, and ORD and PHL can get severely delayed.