well, I'm from Dubai I'm not in the airline industry.
HOWEVER i do have close friends in both arilines & EK as well. What can be safely said is this: Qatar & EY are well established but have image problems as compared to EK. EY just won best airline of the year taking that title away from EK which could mean that they are doing something right..With regards to CC, as i read earlier, if the person who wasnt happy with the previous company is very unlikely to be satified no matter where they go. The people I know are satified with their respective airlines but do whine occasionally!
AS they say, one man's meat is another man's poison! so go with what u feel is best for you!
All the best!