I have that MB 8 months now and it has not missed a beat (yet). Its performance is more than enough for my needs. I would recommend it as its a lot of processing power for the price (with reliability). The nice thing about it you can add daughter boards too.
I pulled out and removed the entire factory radio, 6 disc CD changer and the small 5 channel amplifier (I could not reuse because of the built in DSP in the amp). The PC is where the CD changer used to be.
As the car already has 5 excellent speakers including a 10" sub as standard, I purchased 2 amplifiers to power them. The sound is even better than the 'stock' radio