Chaps just a quick two cents.
The MPL training is a fantastic experience, it will provide you with amazing Multi crew experience and scenarios in the sim that CPL/IR guys will never have exposure to. The learning curve is steep, the standards expected high and it will be a challenge (as any flight training is).
However....
The MPL is still in its infancy and there are many creases. If the worst were to happen and you face a long spell in a hold pool etc. you WILL NOT be able to fly professionally single crew and the route to being able to do so is tough and expensive, consider that when you have just spent 100,000k for that license. If you don't have a type rating you don't have a license, all those tests you pass mean absolutely squat. All of the things put in place by the CAA to allow a MPL conversion do not exist until you complete that TR. Even then only when you pass your first line check after line training will your license be derestricted from the parent airline. There will be no dispensations. Don't be suckered into doing an MPL by a flying school marketing man. Go in eyes wide open, and going in to the future I believe the MPL will be the way forward.
Don't take this as MPL Bashing or negativity toward this scheme, it's good to see Qatar opening the door, just be aware and make informed decisions. Read CAP 804 and have a back up plan.
Best of luck to all who apply, and best of luck to all those successful!