Yes lets have more and better detox facilities, but you will still have better return from an SIS.
Not if addiction is prolonged because addicts are more comfortable continuing in their addiction. A shortage of detox beds will make this outcome more likely.
Most significant is the money saved in the health care system due to fewer infections is far more than what is spent on SISs.
This argument I agree with but I am more concerned with saving lives by getting addicts clean.