Dave,
You're gonna run yourself nuts if you keep micro-analyzing & trying to determine minute & irrelevant differences between different bullets, calibers, velocities & sound levels.
Neither load you mention would give you any detectable difference in terminal performance based on velocity differences.
You'll find + or - variations of up to 50 FPS in either round between a Glock 17and 4-inch published test barrel figures, and can easily run into 25 or more FPS differences with either round between two different Glock 17s, and even at different times of the day.
The Gold Dot may expand fractionally better, the Hornady may penetrate fractionally deeper.
Either one would be adequate if you can shoot the gun well.
Pick something & settle down with it.
Denis