I use the big brother (PA-Y6) daily for a Nexus 5X and a Nexus 6P and have also used the little brother (PA-Y4) and am absolutely satisfied with both - charge the Nexi quickly (Quick Charge), and it doesn't matter if the other ports are all busy. So I assume that this is also the case with the PA-Y5 (I'd be surprised if it isn't, as Aukey is reliable in this respect).

Just use the right cable - because that's what matters. The cable supplied with the Nexus 5X and the cable supplied with the PA-Y4/6 work fine.