Pros
Nothing intellectually challenging as other more reputable research institute, which is important for some people. How ever, you can get busy doing grunt work like making slides, hours after hours, although no one check your charts or figures.
Cons
Since most of research institute already know what Milken Institute is about (Please refer to 'resurrection of Michael Milken' in 'American Prospect”), it is very hard to find a job in a reputable research institute after working here! There used to be an opportunity to build your research portfolio with legitimate researchers here, however, they are all gone. ('Fellows" listed on the website are people who chose to leave Milken Institute, most of which because they cannot take the stigma any more)