We've usually flown on American airlines for both our arrival and return flights.
Checking end of March flights for 2024 and I don't see any flights leaving MKE connecting in CLT arriving in SXM the same day. Not to mention how expensive all the flights are. Have any of you flown to SXM on Delta with a return on American Airlines? Are there any drawbacks using two different airlines? You may ask why don't we just fly Delta for the arrival and return? Because it's almost $300 cheaper doing it this way.

Thanks for your help.