d0zer, both are very high quality. HoC has only aired one season, so it's easy to burn through, and not feel overwhelmed. Boardwalk is the better show imo. It's just so expansive, and does an amazing job with the economy of screentime-- on the level of Game of Thrones. Every scene has value, and the world is incredibly fleshed out. But nothing should be taken from House of Cards. It's a very compelling political thriller, with top tier performances and production.

So, yeah, I won't pick one for you, but hopefully that helps you pick.