i mainly see the prices but i can compromise on comfort only to a certain extent. for eg. if it is a long distance flight then i see comfort and not the price and if it is shorter distance then i buy the cheapest available
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To be frank I prefer to use my local airport rather than Heathrow in London so am governed by the operators who fly from there. As a consequence I use only Emirates who have an excellent reputation and find their service to be first class and now belong to their frequent flyer programme so I now get a few free air miles. With them I can also choose my seat from the comfort of my home computer. British Airways would be only slightly cheaper but I would have the expense of travelling to London and all the mental stress of Heathrow (no thanks).