I don't disagree it's a great company, good job and decent package but the figures you are quoting of take home £4500 plus a month makes it the best paid year one F/O job in the U.K.
I would say your loan repayment is more than 350 a month. People are asking what they can expect to take home if they took the job now, your pay is not representative of what new joiners will expect, telling them what you earn is irrelevant, what they want to know is what they will earn and for that they can refer to my figures above. (You are welcome to correct me on the figures but I am 100% sure they are correct).