FlyerTalk Evangelist
Join Date: Aug 2011
Location: Barcelona, London, on a plane
Programs: BA Silver, TK E+, AA PP, Hyatt Globalist, Marriott LT Plat, Hilton Diamond
Posts: 13,051
Vueling is like any other European low cost carrier. You won't receive any Oneworld miles or status benefits. Vueling Club will only get you a handful of Avios.
Generally new planes in a dense configuration. Charging for everything from seat assignments to luggage. Charging even more if you arrive to the airport without having done your homework. Not a great reputation for on-time arrival and can really go bad during peak travel periods. If checking luggage at BCN you need to arrive very early for your flight.
You're not really spoiled for choice on domestic Spanish routes that avoid Madrid. The train, Vueling or Ryanair. Each has substantial disadvantages...
Instead of trying to "lower the fare", you should be conscious of buying everything you will need during the booking process and not getting drawn in by cheap headline prices.