My G17.5 came with the Ameriglo night sights and they are definitely a bit taller than previous generation Glock OEM sights.
I have also installed standard Glock night sights and Trijicon's (6.5mm rear) out of curiosity and can confirm that they are both POA/POI, just like previous generations. Not sure about Mepro's, I didn't get around to swapping them over yet but I do know the Mepro rear is a bit taller than the standard 6.5mm.
The Gen.5 OEM plastic sights are definitely tad taller than previous generations and have a wider rear notch. It really doesn't matter that they are taller because both the front and rear are taller, so they align properly.
A good example of sight height can be found on the Dawson Precision page, I can't explain it near as well as they do.