've enjoyed the helpful replies. Another question, just get the one with internal lock or order the one without? I live in Pennsylvania so there's no restriction as far as I've found.
I personally am not worried that it will "lock up" or anything in a SD situation. Although it may be unsightly and unnecessary, I don't have a problem with it providing there's not a good reason not have it.
The internal lock seems like a good idea if you have kids. However, consider if you lock it at home to make it safe and you forget to unlock it when you put it in your pocket for carry.