Jim, at your request, I looked at the website of the legal expense coverage referenced in your original post. This coverage is not insurance per se, insofar as it is a prepaid legal plan, as far as I can tell. This is not the same issue as was addressed in the other thread about coverage of civil liability by your homeowners/umbrella policy.
As I read the FAQ on the policy you are thinking about, they essentially just provide reimbursement of criminal defense legal expenses through the decision of whether to indict you for a crime or not. Hopefully, this attorney is able to influence whether the Grand Jury returns an indictment or not. If you are indicted, you are on your own from that point forward, and they don't seem to offer any sort of coverage for subsequent criminal defense nor any coverage for civil liability for a self-defense shooting. Not being a Texas resident and knowing nothing about Texas criminal procedure, I cannot really comment if this is a good deal or not.
I am now in my mid-40's, and I have had a carry permit since 21, the minimum age allowed by Washington state law.