BIEG (Egillstadir) is indeed a nice, neat, quiet, friendly airport that I have used 3 times IIRC. However, I once arrived a few years ago outside 'normal office hours' and was apologetically relieved of a goodly sum for Customs clearance; $100 US rings a bell .. but might well have been more ! Might be worth checking this before takeoff. TKS fluid also eye-wateringly expensive in Iceland to the extent that I have baulked at ever buying any there.