A lot of us have passed on this; but there's always someone willing to underbid.
As for taxes, you need to ask about the 60 day rule. Anybody planning on paying overseas tax need to consider that every time those 10 wheels touch the pavement at home, it's considered a day for tax-purposes. 4 trips a month through Europe; two calender days each time. That's 8 days a month just in layovers. Multiplied by 12 months that's 96 days a year in layovers. Never mind vacations and visits.
Which leaves you paying full income tax in Europe if you're European, regardless of where you actually live. And trust me; they have their eyes on this one.