Horizontal works great, except in my case having a 31" wasit, I just don't have enough cushion to hold something that long and straight on my side. too much curve, not enough real estate. haha It depends on your prefs and your build. Pick what works for ya. I do like horizontals too though. Here's another option.. an IWB holster for better concealment if needed:
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(FoxX kydex IWB single stack holster for Beretta nano pictured)