My .02-- The only way to truly conceal a pistol if you're wearing your shirt tucked in, is in your pocket. I also like pocket carry because the gun is readily accessible and there's no indication. If I'm walking or standing, I have one hand in a front pocket-- a perfectly natural stance-- but there's no evidence that when my hand comes out of my pocket it could be holding a gun. That has to be faster than reaching for a gun in an ankle holster or IWB holster.
If you're sitting at a desk, getting a gun out of a pocket holster is a different matter, but there are other alternatives and you don't have to carry in the same place all the time. The question is, if you were sitting at your desk and needed to access your gun, which would be faster, standing up and reaching in your pocket, or pulling it out of a concealed holster somewhere else?
As is usually the case, there's no single answer that provides the best solution for all situations. As for your choice of gun, I'm not particularly fond of DAO triggers, but it's probably the best option for a pocket gun. When you pull it out, all you need to do if pull the trigger. I really like the Sig P238, but I'm not really excited about the carry options (cocked and locked). Even if it's just as safe as DAO, it requires two separate operations to fire- safety off, pull the trigger. That's easy enough when you're not under pressure, but could be a problem in a situation where you had to react quickly.