I'll try and make this short. This is my opinion based on shooting lots of guns over the years. Some of you may know that I was having problems with my Gen 3 G26 in regards to slide bite. Today I traded in for a brand new Gen 4. I got in my car, swapped the medium backstrap beavertail and loaded the 12 + 1 I had that I unloaded from my Gen 3 without a second thought. Got home and ran 100 problem free rounds through the new gun just to get a feel with the aforementioned BT. Point is, any new modern name brand gun in this day and age is 99.9% going to work out of the box. Chances are actually more likely that a brand new unfired gun is more likely to work than one you've put 10k rounds through. All that to say be realistic. I had no problem holstering up a unfired out of the box gun, and when I got home it proved me right. Any gun can MF at any time. Practice and plan accordingly.