Using cannabis as an aid to meditation?

I practice vipassana meditation and I've found that when I do it after I've smoked I'm able to feel my sensations more intensely and I more easily lose my sense of body. I feel great after these sessions and i'm able to go more deeply than i normally can. however at the same time I'm a little afraid about going deeper than what I'm ready for since its acts as a "meditation performance enhancing drug" if you will. Has anyone else combined the two and what are your thoughts? thanks