I have used Ryanair several times, and provided you are careful, they are excellent! The accommodation is basic, with adequate legroom, but no free drinks or other frills. The staff are efficient, and every flight I have taken has arrived on time or early, even if take-off has been delayed.
But you MUST be careful when booking. I have a friend, always called Barry, so I put 'Barry' on the booking form. As his name is actually John (I didn't think!!) and as the name had to match the passport, it cost me �36 to change the name, so a return flight to Carcassonne of �84 for four passengers, became �120. Zero tolerance on ANY alterations or mistakes, and they cost you! You also need to have alternate dates and flying times (if possible) to find the best prices.
But if you are careful, they are worth using.
Mairzydotes