Cal,
I carry a large bowie which has a 10 inch blade and close to 6 inch handle in a kydex version of that sheath (concealed). It is a great way to carry larger blades and the only way I personally like to carry them. The stud allows endless angles of positioning as well as easy removal at any time. While the handle can take a bit of getting used to, if the sheath is properly designed it won't take long and you'll barely know it is there. Even when sitting (keep in mind this is with the sheath inside my shirt and pants), the stud allows me to sit and the sheath will ride up slightly to allow you to sit, while still being inside the belt. When standing I can push it back down in to place with my forearm rather discreetly so no one is the wiser.
In order to draw it I was taught a cav draw. It is a technique I've read was for pistols being drawn on horseback (thus cav is short for cavalry). It is done because of the limitations on shoulder articulation for drawing longer blades. You don't draw a bowie in a reverse grip, it loses any and all of its advantages as a fighting blade in that manner. If you try to draw the blade in saber grip (assuming from the same side of the body as the arm you are drawing with) with the thumb forward....longer blades will not clear the sheath before your shoulder can not come up any further. You'll essentially 'chicken wing' and be stuck.
Cav draw is when you rotate the thumb in towards the body and grasp the handle with the thumb backwards (back of the hand towards your body). As you pull up the blade your arm naturally pulls the blade up and forward while also wanting to rotate your wrist back to a neutral position, which also pulls the knife around to the forward position and in to proper position.
In re-reading this, it sounds more complicated than it really is. If this is unclear, let me know and I will see about making a quick video of it.