Budget airlines offer great deals when you travel around Europe, but there are plenty of strings attached. The airport might be a long way away from the city. Ryanair operates many flights to Paris, but not to Charles de Gaulle, the main airport, but to Paris-Beauvais, 85 kilometres north-northwest of Paris.
Low-cost carriers that service Rome and London also use alternative airports rather than the main city airports, which can mean longer commutes aboard inferior public transport, more crowded terminals and slower immigration processing. Typical of the alternative airports that low-cost carriers prefer, Rome's Ciampino Airport is distinguished by a scarcity of seating, shopping and toilets, minimal food and beverage outlets, and queues for everything.
Since air bridges that connect aircraft to terminals incur a higher fee, budget airlines tend to park their aircraft some distance from the terminal. That means you'll probably be bussed out to your aircraft and bussed back at the other end, and it's slow and painful.
Seats on low-cost airlines are among the tightest in the skies. Aboard the single-aisle Boeing 737-800 that is the workhorse of Ryanair's fleet, seat pitch is 76.2 centimetres, width is 43cm. EasyJet goes 2.5cm less with its seat pitch. Vueling is the same on its Airbus A320 and 321 aircraft.
Don't bother reaching for the recline button either. Aboard most budget carriers there isn't one. Inflight entertainment, also nada. There is no seat-back screen, so BYO entertainment. If you want to select your seat, eat or drink, or travel with more check-in baggage, that's another small fee in the pocket of your airline.