I am holding F-1 visa. It was a very bad experience. Canadian Immigration officials were very very unfriendly. They asked me to return to US without admitting me to Canada. I insisted to land, finally, they did process my request.
Coming back to US with F-1 visa for me was tough as well. They asked me to go to an office and asked me many questions. Eventually, they put a F-1 stamp on my I-20 and let me in.
Suggestions: better to go there with a US citizen wife or girlfriend. An H-1 visa hold would help too.
It was a very risky trip.
