My strongest criticism of Ryanair (because I have not suffered them yet, knock on wood) is the pricing model. Americans think that they are modeled on SW but the best feature of SW is that they have an inexpensive full fare ticket.

On Ryanair it is always non-ref and on a sliding scale based on demand. The one time I considered using them the ticket was about SEK 1200 one way for MMX-Hahn. CPH-FRA was fully booked in all classes on LH/SK. It was a Sunday after midsummer. Not exactly cheap. But I didn't want to buy a non-ref ticket because my plans were uncertain and subject to delay. Then 4-5 days out it was close to SEK 2000, so I said to hell with it and took a train CPH-FRA. (At least I didn't have to schlep to/from Hahn and Sturup.) But that train ride was no picnic, I tell you!