Hi,
I just had some experience with the Pioneer P4600MP and P7600MP that
you may be interested in.  I originally bought the 4600 and discovered that
it does not have any way to adjust the brightness of that blue backlit  
display,
nor did it have the ability to auto-dim when using your headlights.
Looks fine in the daytime but I found it way too strong at night.  I took  
it back
and got the 7600.  The P7600MP has
another wire that the 4600 does not have, that is, an orange/white wire  
that is
the "illumination" lead.  This causes the 7600's display to dim slightly  
when
you turn on your parking lights or headlights, if wired to the car's  
illumination
lead.  Also, the 7600 has 15 display brightness adjustment levels.

I do know that the 7600 supports Pioneer's wired remote control which I  
think
is a steering wheel mounted control.  I don't know about OEM remotes and
didn't have the issue because my '98 Avalon did not come with steering  
wheel
remote.
Note also that both the 4600 and 7600 come with a wireless remote control.

I had the 4600 installed by an installer (Best Buy) but I watched and now  
understand how
it is done.  After returning my 4600, I purchased a 7600 elsewhere and  
installed
it myself.   My Avalon has a separate amplifier that drives 4 speakers  
plus a factory
sub.   This required
an "amp integration harness" made for Toyotas that have this setup.  Then  
the
preamp outputs of the Pioneer are connected to this harness along with all  
the
other wires, without having to cut the original harness.  You might have a  
separate
amp and need a similar type of harness.  Otherwise, a normal harness made  
for
connecting Pioneer to Honda will make it much easier.  I know Best Buy  
carries
these for $8 - $15.

I found some good info about how to do this from
http://www.carstereohelp.com/stereoremoval.htm

I think you have the choice of mounting the unit using the factory  
brackets and
using screws into the sides of the Pioneer, or using a "front" type mount.
It includes what you need to mount it either way.
My 7600 is mounted to the factory brackets.  I had leftover in the retail  
box
a metal sleeve used when doing the "front" type mount, and a plastic trim  
piece
that wasn't required in my setup due to the dashboard trim.

Good luck.