AS uses the 738 on the SEA-MIA, MCO runs, which are pretty long. They need to get the 700 version ETOPS certified. It will benefit them in the long run. In my opinion, AS uses the 737 like it was designed to be used, short to medium long haul routes. What is needs to order are the 739ER, and 737ER versions for more range and capacity.
Hunterton