I am trying to book a trip to Belize via Miami and have been reading a lot about long queues at Miami Intl. At present the return flight I am looking at from Belize is BZE-MIA and then MIA-LHR with a connecting time of 2.5h. I am not sure if we will have to collect bags or if they will be transferred (travelling AA). The question is: will this be enough time. I have only travelled within the US before and have never made an international connection in the US besides coming from the UK. I am assuming I will have to go through customs and pick up the bag. Otherwise I could get an early flight from BZE and have a >5h connection time.