From my quite extensive experience (I had a high-end car stereo shop back in the days...):
Wattage doesn't mean much in itself. Don't choose a head unit based on rated power only.
The stock units, either the Blaupunkt or the Alpine, are extremely well built units with very good sound quality.
I doubt you will find anything on the market today that can compare with it, unless you are willing to spend serious $$$.
The stock amplifier is capable of driving the speakers to more than reasonable listening levels even with the top down at freeway speeds.
It was designed to match the stock speakers and the acoustics of the car.
None of the after-market units will be able to match quite as well, unless you are willing to spend very serious $$$ again for a high-end DSP.
Even that, won't have the warmth and character of the analog stock units.
If you need bluetooth, search this forum for several options of converting the stock unit to support bluetooth.
Just my 5 cents