I have one and put 45 degree offset iron sights on, which might prove helpful for 25 yds and under, even if the Vortex is working just fine. The 3X optic excels in the 50-250 yd range, which is not exactly a home defense range.
Aside from the above, you won't be able to use cowitness backup sights as the magnified optic prevents this (unless you have a quick disconnect to take it off). You need a 1X optic to cowitness.
Also, you have to put the rear iron sight in front of the Vortex as the Vortex (and most prismatic scopes) has such a short eye relief (like 2.5 inches). You need to place the Vortex at the very rear of the picatinny rail.
Another thing you might consider is a laser to aid in CQB, using it judiciously (not giving away your position if relevant). I have one that's integral to my light.
One last thought, you can keep the front cap closed, turn on the reticle illumination, shoot with both eyes open, and it will work like a red dot to some degree, especially after practice. In that case, the Vortex will be of benefit under 25yds. The brain melds the reticle with vision from the non dominant eye, overlaying the reticle.