FN 509 9mm vs Glock G45 Gen5 9mm

These two land almost on top of each other on paper: both are striker-fired polymer 9mm crossovers at 17 rounds, within 0.02" on barrel length (4.02" vs 4.0"), 0.04" on overall length (7.44" vs 7.4"), 0.01" on width (1.34" vs 1.35") and $8 on MSRP ($647 vs $639). What separates them is weight and sight radius: the Glock G45 Gen5 9mm is 2.42 oz lighter (24.48 oz vs 26.9 oz) with a 0.23" longer sight radius (6.02" vs 5.79"), while the FN 509 9mm has the lighter trigger at 5.5 lb vs 5.8 lb and luminescent 3-dot sights front and rear. Neither of these configurations is optic-ready.

Pick the FN 509 if:

• You want the lighter pull — 5.5 lb vs 5.8 lb
• Luminescent 3-dot front and rear sights are worth having without a sight swap
• You prefer a stainless steel slide and 0.09" more grip height (5.56" vs 5.47") to fill the hand

Pick the Glock G45 Gen5 if:

• Carry weight matters: 24.48 oz vs 26.9 oz, a 2.42 oz saving on the belt
• You want the longer 6.02" sight radius against 5.79" for iron-sight precision
• Three magazines ship in the box rather than two

Capacity, length, width and price are close enough to be a wash, so this comes down to 2.42 oz of carry weight and a longer sight radius against a 0.3 lb lighter trigger and luminescent factory sights. If a red dot is the plan, neither of these two is cut for one as listed.