Sorry to disapoint you but Easy jet started with 737-300s, like most other lows cost set ups, I think the only real option is a 737 as they are reliable, have a set of airstairs which is a lot quicker than an airbridge, you can load and unload by hand, and are quicker to refuel than a 320, which is one of the main reasons all the low cost airlines use them. I think airbus would have to have pretty good price package on the table before the enter the low cost seen.
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