I''ve never had any trouble exchanging travellers cheques in Kalkan, although the post office stopped doing this about 3 years ago (maybe now they have had a refurb this year they will start this service again). I now tend to change either at Abi Tour or at Infinity Jewellers next door. However, I know that there are others out there that will also change them. I do find this the safest way of taking money abroad still, though some of the EK members use a Nationwide card which seems a pretty good deal.