Garmin Oregon or Dakota ?
 

Hi everybody. I'm planning to buy a GPS for a 6 month trip next year (inkl russia, mongolia, khasakstan).

As I'm new to this, it would be great to have some help from people in the know.

I think I want to but a Garmin from the Oregon or Dakota series, because they are small, waterrproof and run with AA chargeable batteries.

Can anybody tell me what is really needed because there a many different versions.

thanks in advance