The short answer is a question: which sounds better to you?
Some people prefer directed sound from their surrounds. Others (including myself) enjoy a bit more nebulous origin for surround effects. I suppose the most obvious difference is that the former group tends to listen to multichannel music; whereas the latter uses surrounds more for movie effects.
I have to say I enjoy the illusion when I'm watching "Rise of the Guardians" with my daughter that Pitch is flying around the room, and it's unclear where exactly he is as his voice pans around -- just as the visual cues only show a flicker of a tail of a shadow during those moments. It seems pretty authentic in that type of scene. My bipolar rear surrounds are perfect for that sort of thing.
But that's not to say they sound muddy. A door closing or a dog barking over my shoulder still sounds from a single point of origin. Still, I'm sure if I were listening to a concert in 5.1, bookshelfs as side surrounds would probably sound better.
Your friend's speaker positioning seems pretty dubious, though. Speaker makers usually try to keep the off-axis response as close as possible to the on-axis response up to about a 45-degree angle. Beyond that, and you can only hear reflections -- especially from the tweeters. Whoever sits in the middle of your friend's couch is pretty much screwed out of the surround effects. And whoever sits on the left side is screwed out of the right channel effects, and vice versa. He really ought to toe those things in.
Then again, if he's happy, who are you and I to tell him his ears are broken?