Originally Posted by DRTBYK
As it pertains to Garmin Map Products, you should only purchase the DVD. This will enable you to install the maps onto any computer and use them in BaseCamp without having to have the GPS they are also installed on connected. I don't purchase many of Garmin's map products (CNNA the exception) any longer as the OSM maps are getting very good in most areas of the world.
You might want to do a little more homework on the Montana and BaseCamp/MapInstall. You can load as many map products as you have space for (32GB is the max µSD Card supported).
The recent Garmin DVDs are locked. Its currently $75 per extra unlock key. If you buy a new Garmin device and you have two DVDs, you get to fork out an extra $150 on top of the cost of the new device. Ouch. With the chips, they may be slow to load in Basecamp and easy to misplace, but it costs nothing to move from device to device. For me, that makes the chips a better deal. Then again, the devices only have a single chip slot, so if you have a City Navigator and a Topo chip you must pick one... MapInstall doesn't help you there.
You are right, the OS maps are getting very good. The NZ Open GPS project is fantastic, for example. However, although the map is in some cases more up to date than Garmins' map, it doesn't contain topo data. For offroading, its really great to be able to see elevation data.
The rest of your comments are subjective and all opinions are valid
Good point. Here's just the factual data:
* Doesn't have a fuel odometer, or multiple trip odometers, or low fuel warning.
* The onscreen layout has smaller buttons than the Zumo.
* Doesn't come loaded with city navigator maps.
* Doesn't give junction previews
* Thicker and heavier than the 350LM
* Same road disappearance issue as the 550 (the Montana shows more details, important offroad)
* Screen is less bright than the Montana
* No Garmin connect support
* No custom map support
* No BirdsEye satellite imagery support