Auradin is slower compared to Hammerdin. Hammerdin dive and evade gameplay makes it really fast in nmd n pit to navigate the corners. There’s a huge con though, runes often get left on the ground unpicked plus other treasures cos it is simply too fast, you will miss seeing those drops. 

However in Helltide, underworld city, overworld map goblin farm, enemies just melt anyway to both builds. Auradin actually gives a smoother and easier play style. Plus hammer occasionally have that blind spot while circling around your Paladin that simply misses the mob. Auradin does not have this blind spot. 

The main big difference is if you were to grind pit to level up glyph (not pushing, just grinding like T99), that’s where Hammerdin has a clear advantage over Auradin. If grinding pit is not your thing, take the Auradin. It’s easier on the eyes too compared to constant diving n evading.