If you fly 50hrs a year then you spend at least £5000 a year on flying
Depends what you fly - I do appx. 200 hours/year, but TCO for 50 hours would be c. £30k
Re headsets, you pays your money, you takes your choice. I like the best I can afford and for me Bose has always offered the most effective solution, if not necessarily the best value. I use A20s with Bluetooth and I'm extremely satisfied with them.