I used to love Frontier... and I used to fly Frontier DEN-MDW and back on a regular basis until two years ago when they delayed one of my flights for 5 hours without any updates and no assistance (no one at the counter). They cancelled the last flight (following mine) before they cancelled my flight so those customers booked up all other available flights and cars. My flight was supposedly cancelled due to weather and the other flight was cancelled due to mechanical issues. When I called them, they couldn't get me on another flight for 5 days so I found one last car, a couple of people (from the other flight) and we drove. I only received a credit for my flight while they got a credit and a refund for the car/gas/ and some other benefits. I didn't appreciate any of it. I don't care for the $20 bag charge and they significantly reduced my options for flying my route. I've had no problems with Southwest, I don't have to pay for luggage, I have many flights to choose from on any given day, the prices are low, and I get to pick my own seats. It would be sad to see a denver airline go out of business but for me SW just makes more sense.