Fobus is fine for training. Because the paddle rides down in the pants you will probably want to wear it behind the hip bone, basically along the seam of the pants. If it's much further forward it will inhibit bending and getting into the front pockets.
The best actual belt carry mag pouch for actual use for me is a Blackie Collins pouch I bought which can be carried horizontally, which conceals well. Even if it shows is just looks like a knife or cell phone pouch, since the flap completely covers the mag. I use it for a 26; I don't know if the 30 mag would fit or not.