Im wildly sorry that I resurrected an old topic from the dead, just have a few interesting observations from personal experience, maybe someone will need this information in the future.
Just my opinion, and worth exactly what you paid for it, but I would avoid using any internal gun pockets, or purchasing jackets with them as a feature.
All that I have ever tried will make the jacket sag appreciably, even with the lightweight micro .380s that weigh in the 10-13 oz. range. Not to mention poor retention and positioning of the gun in the pocket or "pocket holster".
I simply use any jacket or vest that I own as a cover garment. They will all work for IWB carry, may need a little longer (what we call "barn/chore jackets") for OWB, or consider a high-ride holster like the Sparks TK-1; obviously, a shorter slide can be concealed easier, with a shorter jacket, OWB than a full size service model.
our main choice is between "jacket you intend to wear all the time" and "jacket you will take off indoors." When it's below zero outside and 80F indoors, the parka or flight jacket has to come off, which makes it useless for concealment.
While they're not particularly fashionable in most places nowadays, the old-school "spors coat" is cut loose, normally has a single button which need not always be done up, and is generally very light weight, intended to be worn indoors or in hot weather as part of "a suit of clothes." You're supposed to wear a proper "overcoat" over a suit; those tend to be cut fairly long.
Sartorially, a sports coat is worn with a button-up shirt and no tie; a turtleneck is acceptable. Designer T-shirts are considered tacky. Sports coats are "singles" and don't have to match the pants, unlike a suit.
Of course, people might think you're a doorman or a wino if you go about wearing one, but your gun will be acceptably concealed.There are a lot of useful videos on this topic on Youtube. I'll leave one here for general information, I hope this helps someone
https://www.youtube.com/watch?v=jlSw0CJu3sw