So, I had before my Slim also an Xbox 360 Premium, so I can say in a direct comparison, the new Xbox is just a dream. The most important factor, the volume is now finally in a reasonable range, even if you start a game from DVD, otherwise yes "almost" everything as it remained a top console halt!
By design, I like the new Xbox also very good, only the Klavielackoptik is very susceptible to dust, but they, of course fits perfectly :) for all new flat screens.
For noisy power supply, I can only say out loud was the old XBox: D, the power supply is indeed audible but not like here some users write extremely loud. During gaming or watch DVD you can not hear it!
All in all, the new Xbox very successful and a strong buy recommendation !!