I thought Southwest was bordering on ghetto, but Spirit makes it look like British Airways.  It was .... barely serviceable for the price.  It was a short trip to Vegas, but it smelled a little like the public parking lots in Santa Monica - namely, urine.  The seats reminded me of folding chairs with a worn-out cushion.  There's a charge, it was $25 as I recall, for any carry-on bag other than a personal item, not to mention the charge for checked items.