The problem these days with Spirit (not that they were ever great to start with
) is that they are trying to mimic RyanAir in Europe with all of the fees. Unfortunately everything else has kind of gone right down hill with it.
I've spent many years in the airline industry, and very little scares me, but I will say that there are two airlines that I will never set foot on, one of which is Spirit (the other is Cayman Airways).