Really doesn't work that well with the ULCC business model. When you have a business model that generates over 50% of the revenue via ancillary fees, you want to shuffle as many people on and off the plane as possible. Long haul doesn't do that. You'd make more money flying a 320 4 short legs than a 330 on just one leg. 4x the bag fees, 4x the seat fees etc.

The other problem is utilization. When the aircraft are all on monthly lease payments you need to run as many flights/ hours as possible. Again, doesn't work well easily for long haul flights.

Long haul low cost has been a major problem or a flat out failure business model. If the big, experience jet is only going to fly 1 or 2 legs a day, it needs the mega expensive 1st class revenue