The 777-300 seems to be quite unsuitable outside Asia, where there are bigger loads on trunk routes. The 777-300 has less range in long-haul ops than the -200, like the 767-300 has shorter legs than it's -200 brother. Perhaps there is a resistance to stretching existing types, as the 757-300 seems to doing extremely badly (Condor, Icelandair, Arkia, a few aircraft for each, not very promising). Boeing are in danger of assuming McDD's role with Airbus taking the technical and sales initiative as Boeing themselves once did, while now Boeing stretch old types (757-300) like McDD did (the DC9 becoming the MD80, DC10 becoming the MD11) while Airbus build new designs (A330/A340, A3XX).
fly Saha Air 707s daily from Tehran's downtown Mehrabad to Mashhad, Kish Island and Ahwaz