I have a great friend that lives here in MO and uses the LEO CCW permit to carry. He has had zero issues. Note that MO law allows CCW except in prohibited places or posted places. If you CCW in those places and are spotted they have to ask you to leave first. If you don't leave when law enforcementarrives youwill be ticketed. It escalates from there.
OC is regulated at the local level with nostate preemption protection. Large metro areas with many intertwining city boundaries make it difficult to know when you are or are notwithin the law to OC. And there is no good database on small towns, etc. Where are your MO travels going to be located at?