So hop on the internet and do your research. Is hwat I did back almost 9 yrs ago. I tired a few before I chose.

I now own several GPS systems and each has it value andtheir drawbacks.

For an all around system which gives you the capability to load Topo maps, hear the Norad weather no mater where your are in any state or province and give you a 5W walkie talkie is the Garmin Rino.
I have the 530 cxs which does allow one to add more memory. I have added a 1 gig microchip.

I have an old Garmin e_map to which I still use. I also have a GPSMAP378 in my truck that can double and be taken out on my boats as it is both Marine and Auto capable and it can use the data cards from thos old emaps I have.

I run GPS tracking systems on each of my dogs and dearly love that. Tells me where the dog is and in what direction if the dog is on point. I even place a tracking collar on the dash of the truck so I can find my way back from any woods I choose to grouse hunt in. Reason I chose Garmin was the feature it worked well in dense woods. I suspect the rest of the industry has caught up now. I also wanted a unit that would be cheap to run, easy to download maps and allows me to save maps. Garmin did that.

On my handheld units whether the old e-map or the Rino 530cxs or Garmin Astro - I can get a full day and then some use out of 2 AA batteries. I do carry a spare set. The Garmin Astro uses a rechargeable battery pack and will last for days as long as you remember to turn it off.

All Garmin Rechargeable units have the capability to be charged from a auto outlet using their car adaptor if they do not use AA batteries.
The Rino and Garmin Astro are somewhat waterproof. The old Garmin e-map is not and I place that in a small Ziploc bag. The e-map fits into my shirt breast pocket nicley. The other two models I have placed a carabiner clip on them so I can tie them to me as not to loose them.

The newer units have a electric compass which is a nice feature.
The track back features are easy to use somewhat. It took time for me to learn them.
The Goto feature is also easy to use.
The GPSMAP378 is actually what I use for a Speedometer in my truck as it is more acurate and the numbers are big and easy to see.
It can find anything you can dream up frm gas stations, to exact addresses, to shopping cneters, you name it. It is all there - truly amazing. I ref High school volleyball and use it to find the high schools.
It talks to me - tells me when to turn. Wife hates it but is she could read a map I would not need it! Exactly what i tild her.

I have played with the new Nuvis and they are more operator friendly than my other units by far. Everything is touch on the screen.
The Garmin Rino gives you a feature that if your buddy has a Rino - you can see on the Map exactly where he or she is. Gives me a good feeling as now my son in law knows where I am. Sorta like help I have fallen down and can't get up feature.

If you plan to upload Topo maps make sure there is enough memeory in your unit to do so. 1gig handes just about everything in a wide area.

I did have a unit that was 24 and not expandable so I got rid of it.\

To me I never leave home without one or two as like you I learned some hard lessons getting turned around in the grouse woods. Most times the adventure of huting is by myself! However I do still carry a compass and always will.
The fun for me now while deer or grouse hunting is to mark the truck and then finding my way back. I will never be lost again as long as those sattelites stay up in the sky!


JW