You might try pprune forum, it's got plenty of European and other foreign based topics and info on there. There are many discussions about MPL and personally I think it's a detriment to the industry.
The airlines like it because they get cheap labour locked into a contract. The pilots who do it are fools because they don't see how they are limiting themselves to future job prospects should their airline careers take a turn for the worst.
Good luck with your research, let us know what you conclude.