It is my understanding that as of just recently, the Full, Mid, and Compact sizes are available with the External Safety, optionally, which, I am assuming was due to Customer or market demand. Maybe S&W felt it was in their best interest from a Liability perspective, but that is a whole other topic that I am not trying to raise.
Unfortunately, it appears I bought mine just a little too soon.

If one were to have a Trigger tuning on this gun, which takes up a lot of the slack in the trigger before it engages and fires, it seems to this newbie that what little there was in the way of safety is greatly diminished.

Mine is the 9-Pro version and also does not have the safety interlock to prevent firing with the Magazine removed.