I use a Garmin GPSMap 60, as I need something that I can take in the bush as well.

I bought the Canada Topo series rather that streets/cities but you could load what you want.
Does not have voice capability and some of the other stuff on the other ones mentioned.
No issues with the screen washing out, I just turn the backlight up.
Can also get an external antenna if needed.
May not be quite what you are looking for but if you plan on using the GPS unit for hiking etc, it would be a good choice.
My only thought, GET COLOUR! or the map will be very hard to read.