well but you only get c miles ... if you buy a coach ticket and upgrade against $ 1300 at the airport to first you get first class miles plus you pay total less, even if you include the free ticket within thailand into the calculation. the only flight where itīs real good value is to lax but nh takes me to lax in f for the same price as tg does in c so i personally donīt see any advantage for me in that promo.