Yes, I would.
I've been in the area of opiate addiction treatment for 12 years and I was initially opposed to supervised injection sites, but 12 years in the field has changed my mind. I think when someone starts treatment right away that is obviously the best outcome.
I'll reiterate what I said in my opening statement, that treatment for any illness doesn't always work right away in medicine. Supervised injection sites would be reserved for people with severe and advanced forms of the illness. Of course, after failing treatment it should not be the first line.