I know people who have been involved with the chinese aviation as well, from what I've heard, there are very good reasons for why they have to fork out that kind of money to have people coming. For a quick economical boost where people squat down and do their business on the sidewalk 10m from a toilet, China might be a good option provided you don't mind having your passport confiscated when not going on a stay-over, on a 5 star cockroach infested hotel, of course.
40% salary increase yes, but try paying your taxes accordingly in Europe and tell me how much is left, tax frauds in Europe usually result in as long imprisonments as manslaughter if we're talking about a typical yearly captain income. Short haul is still seasonal contracts even though they promise you something else.
The wide body gig on THY is still a reasonable gig compared to what's available around. Regarding the 737-fleet however, I wonder what the guys putting up with it are made of.