I mainly travel internationally and am very impressed by the TK product. If I fly 80,000 miles per year, the benefits far outweigh UA or Aegean-see here: http://www.turkishairlines.com/en-us...lite_plus.aspx

I hear that complimentary upgrades are very common for Elite Plus members and the bonus miles, family memberships and other benefits combined with their fast-growing route system make it a better option than Aegean's tiny network.