I would say that within your budget the PX4 is probably the best hammer fired gun available however I am a bit curious why you have striken striker fired guns from your list?
I guess given personal experience in your price range gun the PX4 is still my favorite. the only striker gun compact that even comes close in terms of ergonomics, trigger and recoil management is the Ruger SR9C and it's second in all categories. I would say that the PX4 would be a very good choice for a one gun collection and would serve quite well.
all guns lost in a tragic smelting accident.
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