What games are playable on Nvidia Shield Portable?

I am looking at purchasing a Nvidia Shield, I heard that some games arent playable.  Namely Half Life 2, Portal and Trine 2, I wanted to know from anyone who has played these games on a Nvidia Shield Portable if they are playble the whole way through.

I don't have one, so I have no idea, but this page might be useful as well: http://shield.nvidia.com/android-game-list/

hmm, looked at some other things on Nvidia's site and Trine 2 is only on Nvidia Shield Tablet, so does anyone know if HL2 and Portal playable frame rate wise?