I guess its a matter of what you want to do. If you are planning on going to the great outdoors and finding your way through the desert ther is only the Garmin that I know of that you can buy the right maps for from GPSOZ at mona vale nsw. just to find your way through the cities and highways etc. it depends how many bells and whistles you need (or want) we started with basic navman that was fine in cities  and upgraded to a tom tom go730 mainly for the bigger screen spoken street names and bluetooth. have had no problems with it and you can connect it to your pc to update and even add corrections of your own or campsites etc. Good luck

Hi.

There's lots of them on market.

For what you\we want. A Basic one will do.

Personally I'd touch nothing but a Garmin. I've had them for over 15yrs. Using 4 at miute. So Far None missed a beat.
Not the fanciest or most lolly laden of them. But they go. and mapping pretty good.
Plus...... Very User Friendly.

For bush work. It used to be a Magellan. Or nothing. But Garmin and Tom Tom (I believe) are starting to cover that too. Garmin "Topo". 2 versions.

if you don't mind going under the counter, so to speak. There's a lot to be had. ready unlocked. and programs to convert street. bush maps to SD Cards.

Same as the GPS Units. I just got a Garmin Nuvi 260. New. Unwanted pressie. one month old. $200. Registered \warranted in my name.
Look on EBay..

Have fun
Macka17

Right, I have purchased two of these, and these are my findings

The make, type, etc is not important
The maps provided and those that can operate in it, are very important
The size of the screen is important
Easy of installation, acceptable

Most work on a windows operating system, so I think it would be important to make sure this is the case, when purchasing. As most map providers program for this, it will mean you can "swap" maps, and even update.

The maps are stored on the SD card, which with the right attachment, can be backed up to your computer. Also "other maps" can be downloaded to it

The "maps" are in fact, the software that you use, so some are easy to navigate around, and others painful. At the end of the day, once you are used to the software, its easy. Route planning is not straight forward, but is made easier with a bigger screen. They will not help you to decide where to go, but will get you there, when you tell it where you want to be. The better maps will even tell you which lane to be in on a highway, for turning.

There are "nice" extras, like dual zone, where you can listen to music as you drive and navigate. Bluetooth, where your phone interacts with the unit, and creates a hands free system. Dual Sd cards, with music on one and the maps on the other. Then theres the radio/tv/dvd/Ipod extras, as you need

I am sure there will be controversy over accuracy, but hell, get me within view of something, and I am ok. Most of the recievers are accurate to 10m or so, and if the maps out of date, and a wrong turn is made, I would consider how many wrong turns it has saved before now.

So, these are my thoughts to now. If it helps others, well and good