after the several beta updates in the last two weeks, I tested this again
Jazzpunk: streams excellently, but no controller support
Dark Souls: streams at 0fps (could not even get to the title screen), but *has* controller support (I was able to confirm that the game didn't shut down properly with the controller)
When it works (like with Jazzpunk), it works well. I just need that damn controller support. Can't do mouse and keyboard on the couch
That's what the Steam controller's for.