Hey! I did the QEM with the double degree option at Sciences Po, if you like you can contact me via PM. I think I would recommend you Toulouse if you aim to do a PhD in the US afterwards, for many reasons: QEM does not help you build your background in math (it is more like the first-year economics sequence of a econ grad program but on a Masters level), teaching is very inconsistent in terms of quality across institutions, and you won't be able to develop a consistent relationship with potential letter writers, the program does not really aim to prepare you for a PhD and its administration/organization is a hot mess. I cannot say much about Toulouse, but I have the impression that it is more rigorous and in terms of reputation might be better for US admissions, conditional on doing well and maybe doing a M2/RA-ship in the same place afterwards (I don't think ou would be able to successfully apply already in your M1). Choose QEM only if you trust your quantitative skills already and you think you can be on top of your class because then you can go to the APE Master at Paris School of Economics for the second year, or you stay at UAB from the start, they have some good people whose letters might help you get into US programs. These are just some things to consider, good luck!