Very good solution if you want analog sound.

I bought the adapter, as is specially recommended in the game Rocksmith, to use one of those. I'm HDMI fan, but unfortunately seems HDMI produce a slight audio delay, even with modern plasma sets. The sound from the TV boxes lags so always easy to picture afterwards. That is so far not felt, but at Rocksmith a music game, where it depends on precise timing, it is very disturbing.
So the adapter is plugged into the XBox360, right next to the HDMI connector. With RCA red and white; it then goes directly into the stereo system. The TV turns you down, so you have only stereo sound.
I stress: I made the comparison in the menu of the XBox360. HMDI Sound lags behind the analog signal from the stereo bit. Minimally, but decisively Rocksmith for the game.
Super investment, and I can say that the build quality also allows a higher price. The Microsoft components look valent. But are also more expensive.