Read the Multi Crew Lic write up in Airline Pilot from ALPA. . .
Then make your decision.
It is, in my eyes, another tactic to pay pilots less and less.
MJR, I take it you are not from the US? Have you looked at coming to the US to do your training? Where you can escape user fees, and the like. Of course, housing costs may in the end equal everything all out.
Also, the MPL does not allow PIC'ing. . .so, your dreams of getting in the left seat with a MPL are nil. Except in third world countries where safety is not a huge concern.