Samsung 30 or 20mm pancake

Hello everyone,

I just got my NX20 to complement my Olympus OMD, I wanted to have an APSC sensor since I shoot a lot of high ISO pictures and need a view finder. I also do a lot of street photography and I am contemplating getting either the 20mm because it's wide or the 30mm for the bigger aperture. Which one would you recommend?

Thank you