DeLorme GPS
I have used DeLorme maps and a GPS device for years and have been well satisfied with their quality. So, it was with some anticipation that I purchased the Earthmate BT-20 with the Street Atlas USA Plus 2007. The map software worked quite well as usual. However, the Earthmate BT-20 was not compatible with my Treo 650 with Palm OS or my desk top PC. A lengthy discussion with a DeLorme Tech did not resolve the issue. Also, a review of the GPS forum showed that others were having similar problems.
The Earthmate BT-20 may work on other devices. But, I would do a lot more research before purchase.

Ok for the price
This is a very functional product. It takes a while to learn to use well and the map data or the GPS accuracy are sometimes limited (it often shows you are traveling next to the road and not on it. No problems using with windows XP laptop and Dell Axim. Overall a good value, but you get what you pay for.

Very disappointed
Had high hopes for this product but it if very disappointing. It was almost impossible to get both the maps and the program on my Treo Smartphone. Doesn't really work on the phone because it continually locks up, the only way to start navigating again is to reboot the phone. Go through a 5 minute, completely non-intuitive, routing process. Then wait 3-8 minutes for a simple route to be created (something the other brands do in a few seconds) then hope it does not lock up again within a few blocks (which it will). If you make a wrong turn, you have to either find your way back on track or go through the whole process again. Another problem is sending maps to the phone is cumbersome and you can only send small portions at a time--big portions lock it up. This is completely stupid b/c with a 2GB SD card I should be able to put pretty much the whole country on it. I've used another GPS that had detailed maps of the entire USA on a 1GB card. Bottom line: For use on your Treo, it is completely useless. On the laptop, it does a decent job including the much needed automatic re-routing but the map program for planning routes etc. is very difficult to use. I've own other Delorme products and they were much better that this product. If you have infinite patience and many, many hours to devote to learning how to use this product then it may work well, I have a job and a life and cannot devote nearly enough time to make it very useful.

DeLorme Earthmate BT-20 with Street Atlas USA Plus 2007
The DeLorme Street Atlas Plus installed without problems. I am impressed that it covers the USA and Canada. I am very happy with it.
I set up the Earthmate BT-20 GPS with my Palm TX handheld unit. It was easy to set up as long as the Palm TX unit Bluetooth detected the BT-20. The BT-20 and the Palm TX unit worked fine together. The only problem I encountered was that the Palm TX unit display was not very easy to see in the daylight. I also wish the BT-20 GPS unit had more information in the little manual with it.

Great upgrade from Blue Logger and SA 06'
Controls on top of Street Atlas 07' interface is a plus, phone database is nice, power switch on the the BT-20 is better. I only gave it 4 stars because upgrading from BL was problematic using my faithful PDA. After three calls to Delorme support and one non-defective BT-20 exchange, I'm up, running, and always know my position on the road! The phone database seems to have some addresses mixed up but 95% accurate as far as I can tell to date.