Was my go-to airline until they "went to" the Ultra-low cost model. Their new model made for very unhappy employees, who took it out on passengers for quite awhile after that.
They also started screening ALL bags at the gate for size and if it was a millimeter over, you had to pay up on the spot -- mine never were, but it slowed down boarding significantly.
They quit that after a few days, I THINK...but anyway...that's when I quit flying Frontier and swore to never fly them again.
Having said that they have improved since then and employees seem to be happy now according to news reports and as I said, I think they got more reasonable about bag size etc.
Indeed, just made reservations for my wife on one of their flights today.
But here is a recent article about how they are doing, which gives facts and figures.
http://www.bizjournals.com/denver/n...-airlines-still-last-for-on-time-flights.html