"A" adds black flashing to accentuate potentially dangerous returns.

I spent quite a bit of time with the old Weather Radar, which will be included in my 767 review.  There is something of a simple art to using range and tilt to find the tops of the high stuff.  Mostly you'll be flying above it anyway during cruise.  I haven't seen many 56,000 foot tops like the Air France Airbus ran into in FSX.