The long-term worry is that if the Mintreal police do enforcement of c-36, they will likely utilize the U.S. law enforcement trend of almost exclusively using Backpage to find targets. Backpage does indeed have pimped-out girls, drugged-up girls, and sadly probably some underaged girls, so stings involving Backpage would fall within the "law enforcement priority" guidelines revealed by Canadian law enforcement. There is some history of this even before c-36, as an old post indicated that in the Canadian oil patch, the police once booked "sessions" using backpage to interview some ladies and ask if they were working on their own free will.
Ignoring law enforcement concerns, the agency ladies and independents here on merb are more likely to give better services. They treat this as a business and care about reviews. That is just not as true for most backpage providers.