I put a pretty generic title to cover many bases.  There are lots of threads on this but I always hate appending to the end of an existing thread question when mine is slightly different.  Obviously I know a bit about GPS's and have had a pretty slick Motion LS800 mounted in my truck for a while running Overland Navigator.  Ultimately is was a pretty cool solution.  However I just couldn't accept the amount of real estate it required and it would alienate my wife as we couldn't cuddle while driving, not really...

Anywho, I have been using the Garmin 60csx for a little over a year now.  I cannot complain about it's abilities one bit, does exactly what it was designed for...  However it really wasn't designed as a car navigation unit, more of a handheld.  I really want something with a bigger screen, 5-7" would be dreamy, and have good software available.  In a perfect world I would love to run Overland Navigator but refuse to mount a PC back in my car.  I have seen various older Garmin StreetPilots that look pretty cool, just don't know if they'll support the latest 24K maps from Garmin that I have.  Additionally while dreaming, I love the contour lines (or lack thereof) of the new Garmin Oregon series but feel that I'm right back to the 60csx size screen and will shoot myself if I go that route.

So with all that said, are there any recent options that seem to fit this need that I'm missing?  Any older options that will work?  Really would love to not to have to drop tons of coin on this.  Still keep thinking about the 10" Acer's that I see everywhere for $200ish, but ultimately it has a fat keyboard and it'd take up some space on my dash that I'm not sure I want to give up just yet.

Larry,

There are hundreds of 5-10" tablets on the market that take up no more room than a GPS because they are thin. For example, my EO Tuftab is small enough to mount on the dash. The problem with most computers is the keyboard.

Since I know you are a geek, you could setup XP Embedded as the OS with Overland Navigator running on top as the UI. With XP Embedded, you'd have a system that only has the XP kernel, hardware drivers, and Overland Navigator. None of the XP background services, or excessive UI components. It would boot in a few seconds. It would be a dedicated machine. I'm going to try this with the Asus R2H I just picked up.

With a bluetooth GPS (powered by the care battery) you can get rid of one more wire.

Pimping Overland Navigator for a second... you'll also be able to plug right into your Kenwood D710 and view  APRS positions on-screen.  :)

Craig

Can't wait to see what everyone has to add to this post.  I'm in the same boat, but with another caveat.  I need something with a semi-large screen that is daylight viewable.  And, I would really like something that will allow me to mount it both in the Taco and on the Dakar.

Many bike folks talk highly of the Garmin 550/660 series of GPS's.  Like you, my primarily concern would be whether or not they would accept micro-SDs with 24K topo data, etc.  Here in the outback of eastern WA, I still haven't run into anyone who has any personal experience with the Zumo 550 or 660.  I have no experience with these SDs in a GPS.  But because of my location, I spend more time in northern Idaho and western Montana than in Washington state.  So throw in travel to Hell's Canyon and Enterprise, OR,  and I MAY have to buy SDs covering four states!  Wish they would do these regionally, or do they?

Here is a good source of information from the ADV Rider site: 

http://www.advrider.com/forums/forumdisplay.php?f=37

I'm all ears to see what comes up from the rest of you.

Dale

Craig there is no need to pimp Overland Navigator, I think that would be the ideal software to run. The APRS piece would be cool, if I ever travelled with anybody else who had it.  So far it's been difficult finding folks who even use HAM out here.  I also knew you'd chime in with some good options. I guess I should reconsider the Asus R2H. If I could load everything up like you mentioned it would probably be perfect. Would even consider Linux if I could find the right drivers.

Todd and Dale, I've been on the fence with the Garmin 276/376C and other Garmin units. These units are what really got me to thinking about this. It would be cool to continue using my Garmin Software, however it has many limitations hence the new search.

Dale, Additionally Garmin now offers the 24K topo's in DVD format. I have the west region and it covers WA, OR, CA and NV. Perfect for me, however it looks like you'd be bound to two areas to get Idaho coverage.

buy.garmin.com/shop/shop.do

I just picked up a Magellan Roadmate 1700, 7" touch screen because like Larry, my Delorme PN-40 does exactly what I need it to do off road but for an around town gps it sucks eggs.  Some of the tipping points for the 1700 to me were: it's win ce & quite hackable which means you can boot a lot of other software besides the build in Magellan/AAA on-road OS.  It also has a video input so I was thinking I could put in a backup camera or even an under car cam to watch clearances when self spotting.
I'm also using it to get an idea of whether I really want to mount a tablet in the X and the 7" screen is proving to be quite the mounting task, I can only imagine a 12" tablet.  The stock mount is way too small to attach to the windshield and too high to mount to the dash as the 7" width really does block out a good portion of my forward view if it is above the top of the dash.  My idea for now is to mount a stalk and have it come up right in front of the radio as I don't need to access those buttons often thanks to steering wheel controls.
As for viewing in full sunshine, the screen is plenty bright but not so much that it won't get washed out when in direct sunlight.

Here's a thread that gave some info about the 1700 : www.gpspassion.com/FORUMSEN/topic.asp

As I put the mount together over the next couple weeks (items on order) I'll take pics and put up a build/use thread.

Yep, works perfect and I've tried or considered A LOT of options. The picture above is a little misleding.  I can still see the end of the hood from the drivers position with that setup.  I was leaning over to get a better framed shot when I took that picture.

The EO TufTab I have is slightly underpowered but has plenty of power to keep up with Overland Navigator.  The big selling point is the sunlight visible screen.  It's fantastic.  With a newer model out, they are starting to sell cheaper on ebay now.

I haven't used one.

Those slates that Chip Haven mentioned on ExPo look sweet.

http://www.myviliv.com/ces/main_s5.html

http://www.myviliv.com/eng/product/x70ex.asp

More Viliv S5 goodness...

Not necessarily a Topo app but I have been usung Glue Trail on my Android phones with great success. The app will locate you on the image file of your choice after you affix the map using a Google Maps overlay.