I buy mine from Edmonton on eBay.
The unit have pretty much most of the US lake inside, if you go on simulator and move arround in the US. you will see many lakes with lots of details.
I use auto chart because it allows me create my custom lake where other brand will never go to and also with higher details. I seriously enjoy this new toy and I fish completly diffirent now.
Every anglers should have MAPS when fishing. It help alot and you become a better one too and you have a toy to play at home after your fishing day