Guys I joined one year ago, and trust me everything I heard before I join was not true. Read Black Pudding threads, he mentioned everything you need to know.
I was accepted in the three big gulf carriers and I decided to join QR, and I don't feel regret at all. We have a quite good number of pilots who have been here for many years and not thinking to leave.
The company expects you to do your job as described in your operational manual, so read your books carefuly and you'll get what you want.
The operation is very relaxed, everybody does his job, respect each other and leave happily.
Qatar is still under development and the culture is quite deferent for some, its changing slowly, but remember that we are here to work not to change the country.
For the guys thinking to joing, don't hesitate just come and build up your careers.