After looking at the cost of the dorm with the meal plan I am considering going the apartment route. Does any one have any experience positive or negative with this? Any tips are appreciated.
Depends on where you are from and whether you have any past experience of living alone.
The McGill rez experience is un-comparable. You will make tons of friends and will always have someone to hang out with. There will be floor fellows, dons and staff whom you can ask for help if you have any problems. The residences are tailored for students living on their own for the first time in their lives. There are protocols for rookie mistakes such as locking yourself out of your room, losing your keys etc.
On the other hand if you chose to live off-campus, you will have to find an apartment, negotiate a lease agreement, pay your rent independently (of your other McGill fees) and so on. While locals may be comfortable with doing all this, if you are new to Montreal and Quebec, you may find the process a little daunting and confusing.
Ultimately it depends on what you want. If you want to save a lot of money, and are comfortable with finding and managing an apartment on your own, you could go for off-campus housing. If not, then a rez would be a better (albeit more expensive) option.