I've used a lot of Garmins over the years and they work very well.

However, they all are a pain to set up and remove because someone may want
it and not care what damage is done to your car to get it.  I've had that
happen on my old Ford.  Damage was more than the unit they stole.

Now I've gotten them built-in.  It's always there an running if you need it.
Convenience is a big plus.  Less theft to worry about as well as unplugging,
removing (that dash in the Prius is deep!) and setting up the thing
everytime you get in the car.  Since then, I'll never own another car
without it being built-in.  It integrates to well into the vehicle's
sound/phone system and you can talk to it whereas the portables aren't there
yet.

My two cents.

B~

Any of the PocketPC/GSM Phone/GPS units works fine, if you can live without
the Mac sync business (or maybe it is possible, but I have no need).

The built-in system in the Prius offers a few advantages over a
portable GPS unit.

* uses existing (often larger) display screen, touch and voice
activated
* uses existing audio (mutes radio for directions on driver's speaker)
* has dead-reckoning ability.  The Prius' navigation uses a series of
gyroscopes and the vehicle's speed sensor to know how fast it's going
and of any turns made, and can plot this on the map, even if the
navigation system has lost all satelite contact (such as in a long
tunnel or parking garage complex).
* uses car's own charging system (no batteries to change out or messy
charging cords)
* difficult to steal or accidentially misplace/lose
* single DVD, so no swapping out of discs or memory cards when on a
long trip.  (US/Canada on one DVD, for example)

However, a portable GPS system has a few advantages over the built-in
system in the Prius:
* available often for cheaper than the built-in system
* can be added after purchase
* can be used in other vehicles, or when walking/biking/etc.
* map/POI updates are often easier to get, more frequent updates, and
may be cheaper (if you only update your local area and not the entire
continent as on the Toyota system)
* may have some features (such as breadcrumbs/remembered routes) not
available on the built-in system

Toyota doesn't have update DVDs very often, but they're usually in the
US$250-$300 range...  If you are in Europe/UK, you can lookup DVD
updates and purchase through http://www.toyota-mapupdates.eu/default1.asp

Do note that you cannot easily add the factory Navigation system to a
Prius not already built with it.  (At least 2X the parts cost alone as
compared with the option pricing, let alone a lot of labor...)  So if
you want it, you'll have to order it that way.  US 2007 Prius option
packages #5 NL, #6 NW, Touring #5 NM, #6 NR, all have the factory
navigation included.  If your local dealer/region doesn't offer the #5
NL or NM, you may want to see if your dealer is willing to swap
outside of your region, or else you may want to yourself go out of
your local region to get the package you want.  Try different ZIP
codes in the "build and price your Prius" link on the left side under
"Shopping Tools":
http://www.toyota.com/prius/options.html

Yes, the Toyota system has a speed lockout of most Navigation buttons
when you are moving.  (Home and the 4 or 5 preset destinations still
work, as do various voice commands.)  For 2006, a larger display (with
better resolution) and newer navigation system was added, which
doesn't accept the known screen button hack to allow use of the screen
while in motion, but now does allow destination input by voice
command.  (Voice commands are usually spotty at best.  8(  )

If you really are annoyed by the speed lockout, you could purchase a
Lockpick:
http://www.coastaletech.com/LOCKPICK_MAIN.htm

As to whether a portable unit or the integrated Toyota unit is best,
that is really a personal decision...

What I did what get a Garmin 7500, get the external plug-in antenna and have
someone mount it under the dash in the center by the front window, and hang the
nav in front of the plastic tray with the smokey fold-down plastic piece in the
center of the dash by the front cup holder.  Any good car stereo shop will fix
you up with plug in power and mounting.

Then you have a FAR BETTER nav then the Denso nav that Toyota uses, you can take
it out when you want, and you can update the database over the web with SD
cards.

A bonus to this is that the nav screen doesn't get washed out by the sun, and
you can keep the consumption screen on the regular display together with the nav
screen.  Also, you don't have to put up with the the lockout.

Steve

I purchased an Accord with NAV.  I purchased a Garmin Nuvi 360 for my Pilot
and travel.  I think the Nuvi is more useful than the Accord NAV.  I wish I
had saved my money in the Accord.

Get a portable NAV!

G-Man