I just did some research on Mississippi, since my son is stationed there currently, just turned 21, and wants to get his first CCW.
A MS resident can walk in, fill out and application, pay $100 and get a CCW there. NO TRAINING REQUIRED...... Which is why Nebraska will not honor Mississippi.
Now the cool part about MS, that I've tried to get some Senators to do something similar here in NE........ If you go through a MS approved CCW course, you get a "endorsement" on your permit. Having that endorsement on your permit means that all of the off limits places, ARE NO LONGER OFF LIMITS TO YOU. Except Police stations and jails.