Well I have both myself, Gen 3 is nice, but I bought another Gen 5, my reasons, no finger grooves, better RSA then the one on the Gen 3, and to me, the Gen 5’s have a somewhat better trigger, my input on this
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The Glock 19 Gen 3 vs. Gen 5 Comparison: Are They Really Any Different? - The Mag Life
Is one generation of the Glock 19 drastically superior to the other? I would say no. However, the Gen 5 does have some attractive features that the Gen 3 does not. If I were restricted to using a Gen 3 Glock 19, would I feel disadvantaged? Not at all. While there might be more accurate pistols...