Hey! there are great companies in canada. There is no reason to have to buy from the states.
To answer your question, yes there are customs problems. I have personally tried to order juice and customs will seize or return your order. (In my case they returned it to sender)
Soon there is a new company releasing the most premium E-Juice without the premium price tag. i will let you know once we are open to the public. E-Juice, and also hardware!
www.bestvape.ca