I have to ask...why don't you shoot your AR?
I enjoy, and shoot my 10.5", Aimpoint equipped, Armalite as the CQB end of the spectrum , but also use my 14.5" LMT with ACOG for mid-longer range 'games'.
My non-restricted, rebarreled CX4 in 9MM is a very different animal, but still
a blast to shoot at contact to 75 - 100yrds. Light recoil, 10 round mags...take anywhere ability...a great addition to anyone's battery!
I would recommend seeing if someone will let you 'have a go ' with a Storm before you buy...I find it 'compliments' my AR's, not replaces them!