Garmin GPSMAP 640 Waterproof Car/Marine GPS and Chartplotter | Marine Electronics

So I bought this unit for one purpose, to use it on boats in my boat club. I currently own many of Garmin's products, from nuvis on the street to a GPSMAP 4208 on my own boat. This is a great little GPS. I have been using it in the car until the weather warms up and I can use it in the boat. I would not recommend using the included friction mount. RAM has an awesome windshield mount that works great. As far as functions and usability, I have no issues, everything is where it is on my Nuvi in auto mode and marine mode on my GPS MAP 640. I have a G2 Vision card that I use in my 4208 and I put it in the 640 and I get all the additional map features missing from the base map. For the reviewer who posted about the navigating function moving over land while in the water, that is because you need the G2 Vision card to use auto guidance. I would recommend this GPS to others who need a portable GPS.

I purchased this GPS as a back up to use on my boats and on land when required. I had contacted Garmin to make sure that the inland rivers were a part of the data base. When I received the unit and started using it I found the rivers were not on the unit. I then checked and found an update on the software was available. After reading the instruction, easy to understand, I hooked the unit to my MAC, with the provided cable, and down loaded the updated systemware and the river charts.
The unit meets my expectations at this point and I feel with more use, marine and auto, it will exceed my expectations.

The 640 could/should have been so much better, had Garmin enabled the XM Weather capability in Automotive mode, in addition to the Marine mode, which does support XM Weather (WHY would they do such a stupid thing?!), and kept the Tracks/Tracks Management feature of the 276C/378/478 models, which are also geared toward Marine/Auto users. The unbelievable thing is that these missing features are all features that Garmin has implemented in older units - it is baffling why they would eliminate them in newer models, particularly at a time when this basic GPS functionality in the 640 is so widely available in smartphones. They also reduced the number of saved Routes. As the 640 is currently configured, I will stick to my trusty 478 for a long time, despite the fact that I would have liked to upgrade to a larger screen and updated GPS receiver technology found in the 640.