As someone else said, the problem is the once a week flight. You can save a lot of money with them, so long as you recognize that, and that they charge for everything. They charge for seat assignments. They charge for CARRY ON bags. (In fact, the last I knew, carry on bags cost MORE than checked bags, which is one of the few things they do that makes sense.) They charge to CHECK IN at the counter. Their seat pitch is horrific--NO leg room whatsoever. Possibly they charge to accept credit cards, not sure about that, but a similar carrier, Allegiant does. For the SXM flight, if you save enough money otherwise, it might be worth it for the Big Front Seat. We have used them a couple of times to squeeze in an extra cheap trip to SXM, and we had no issues. The problem would become if there is an equipment issue, you could have a big problem. For a once a year type trip, probably not worth the risk. They do NOT cooperate with any other airlines. One time our flight from Tampa to Atlanta was cancelled on Delta. Because Delta cooperates with other airlines, we were able to switch to US Air (at the time), from Tampa to Charlotte and on to SXM for no extra money. That would not happen with Spirit.