Last week my wife and I went to TG and used Vueling via Barcelona, with a 1 hr stopover each way.
The trip out wasn't bad, though the seats are tight, but otherwise everything went fine. Be warned though that if after going through security at Gatwick you buy any bottles or other restricted items, they will be taken off you at Barcelona, despite the fact you have always been in a security area.
Coming back was a different story . . .
As it is out of holiday season the majority of passengers were Gambian. As many gambians are tall, the seat spacing is totally inadequate. On arrival at Barcelona we were held up for ages whilst every Gambian passport was scrutinised with a magnifying glass. Non-Gambians just had to wait their turn. Then the transit security seemed to be understaffed and the jobsworths there made no attempt to get us through to our connection. This meant that of the 19 people doing Banjul - Gatwick only 6 made it in time and the rest of us watched the plane go. No-one would do anything to get us on it.
After a number of heated discussions with arrogant and unhelpful Vueling staff we were eventually rebooked. No-one even apologised. We then had a 5 hour wait for the next Vueling flight as Vueling won't put held up passengers on a British Airways flight which would have meant only a 2 hour wait. We were given a voucher for a snack and a drink, but that's not much for a 5 hour wait. The final straw came at Gatwick when we found that none of our luggage had arrived and we have just got it back after 3 days. Of course we all lost money in the UK on wasted tickets and taxis which had been booked assuming we would get back on time (our replacement train tickets cost us £128!!) - I suppose we may eventually get some recompense from Vueling . . .
Be warned - if you want to use Vueling (which is cheap!) don't attempt to come back from TG with only an hour between flights - it isn't possible.
We won't use Vueling again!