“I should add that the unit did not come with a disk.”
Garman normally provides downloads to update maps etc. Depending on what you bought.
GarmaN is undoubtedly the best GPS...but some Garman’s are better than others. Military GPS has been Garman, pretty much from the get-go. I will use only Garman. They are accurate. To within a baseball diamond.
The unit was purchased by my wife from a member of our Sunday school class. For some reason he didnt want/ need it. The disk and cables were lost somewhere along the way.