Thank you very much for sheding lights on Penn. I'd say what you mention about Penn is really attractive. As far as I know, the social work program at Penn is quite respected, but the social policy program is relatively new and small program. And it is an one-year program, I hope to accumulate more research experiences during my master studies, so I prefer a two-year program.
I'm interested in labor issues, and my focus is on Chinese labor issues. I don't see any professors at SIPA who share similar interests with me. But at UCLA, MPP program has a clear labor track and related faculty are excellent. I know some big names in this area like Ching Kwan Lee, Ruth M. Milkman, etc. It's very likely for me to work with them in the future. Also Campus resources also include labor related centers like UC Institute for Labor and Employment, UCLA Institue of Industrial Relations, UCLA Center for Labor Research and Education, etc. Finally, I find LA is a good place to study labor issues, because labor movement in California is really more intense than other areas. Those resources really make me believe that UCLA is the best choice compared to other schools.