The bottom line is that YOU need to go to a range rent the different models then YOU decide, or you'll be second guessing yourself forever.
Half the members here will say Gen 3s are the best, and the other half will say they love the Gen 4s...
A quarter will say G19 is the best, another quarter will say G17 is the original, and the other half will say 9mm is for *******... Then you get those 10mm guys...
See where I'm going?
Get what YOU want after you've physically tried them out - don't listen to use too much.
Regardless of your choice, I guarantee you'll be buying a second and third Glock soon after, unless the government only allows us to carry sharp sticks.