Right, I'm interested in policy careers so DC is definitely the place to be. As to the night classes - I don't want to take only SSP classes (otherwise I would have applied to that program) but intend to take the security focus at MASIA, hence my concern was more the quality of faculty and who else is in those cross-listed classes.
I asked my friend who's in the MASIA program now and he said people can just enroll in whatever classes they want, e.g. finance through McDonough or international arbitration at the law school. Apparently the SFS offers a lot of these courses as well though. As for SAIS, there are more mandatory quant courses, plus you get the dual degree with international economics which might stand out to some employers.
The other thing he said re: SAIS is that he hears their programs are very siloed by country whereas MASIA has more crossovers between Korea, China, Japan and SE Asia people.