Most +P 38 special brass is identical to normal 38 special brass. Weight it compared to the same make to be sure. I just use it normally.
Speer is fine brass. I have some from the 70's I am still loading and it has not split yet.
I sort by headstamp and then work up a load for each head stamp. I find that I get better accuracy if I sort the brass vs. just a pile of mixed brass.
10mm and 357sig, the best things to come along since the 38 super!