I'm not a Glock fanboi, despite coming around to and shooting them a fair amount, but for ~$500, you aren't going to get a better full or mid sized 9 than a Gen 5 G17/19. different, yes. Not better.
If you are already leaning towards a Glock, there's not any real reason to shop around. If you have issues with them, like K frame, then sure one of the many similar polymer pistols will likely work. But if the block works for you, just get one of them. There's something to be said for the ease of finding cheap mags, holsters, lights, sights, and anything else you might want.