Since JHP are very expensive and hard to come by in large amount --so how many rounds to you shoot in your R9s and deemed reliable to use and trust your life with it?
I bought a few boxes of speer gold dot 124 grain JHP and plan on trying it out a little bit more but hate to shoot 300 rounds and say ok to use.
If you are breaking in your gun for the first time and testing the gun itself, I would disagree with the previous posters. A gun needs a lot more rounds than that through it before I'll trust my life to it. Especially an abbreviated pistol, which are always more fickle than full sized combat pistols.
If you're just testing a change in ammo, and have already proved the gun, then I'd feel a lot better about shooting 4 or 5 boxes than a single box. There are a lot of reasons for this, consitency from box-to-box is an important one. I will buy boxes of my SD ammo from several different sources and it must perform no matter which box it comes from. If it does, my confidence is greatly enhanced. If not, I continue the search.