Republic used to fly into EYW year round during the days of the Carribbean hub in FLL, but the loads were very, very low in the summer so Airways went to seasonal service out of CLT. 170 never had any issues with performance. We were always able to get out of there with a full load if needed. The only issue in summer was flying around a 170 with 5-15 people on board. I believe the season in from October to April or May. Just check Airways future schedules. I don't think the service is daily during the winter as well.