It may be worth pointing out;
The Garmin Montana 600 is an older model and there are newer recommended alternatives.
There are newer alternative ways other than Basecamp to plot gpx routes and transfer them to possibly all Garmin GPSs and particularly the newer ones
.
Any newcomer could be advised to take a look here
http://www.trf.org.uk/portfolio-item/isnt-there-an-app-for-that/ - and start with GPS for free on a existing smartphone or £50 secondhand Apple or Android- before spending £350 on technology they may struggle with. We are seeing significant numbers of people giving up on GPS because a Garmin is difficult to use. I feel that starting with Viewranger and progressing to Garmin is a better - and cheaper approach.
Eventually it is highly likely that you will end up with Garmin - I am a great fan and have two units- but in my opinion it is not the best place to start.
Many groups run GPS sessions and I would be happy to run one on demand at a local group.