PYL,
CX does have some pretty good trainers who come from a multitude of different backgrounds, but your experience will be limited to the environment in which CX operates. If you are a Hong Kong local, it is a valid way to break into the industry, but it is worth your while to look beyond the horizons of Hong Kong if such options are available.
If you do choose CX, however, there area few pressing issues you must contend to. Besides the long and extended upgrade times due to management decisions to cut costs, the organization is also suffering from some serious cultural problems. Morale is low, and if you haven't figured out from some of the posts here, some of your would-be coworkers may be potentially hostile to you as well. It does not foster a good learning environment, which is a shame, because even if you are enthusiastic for aviation, it has the potential of chipping away at you the wrong way. This may hurt your enthusiasm, and I know a lot of people whose dreams of flying become crushed by this. This likely won't get any better either until some executive actually does their job to turn the ship around, and the workforce starts working as a team again.
Best of luck to whatever you choose though. Having the enthusiasm for flying is really something special, and whatever you do, don't let others take it away from you.