Faster but in the summer with vacationers RVs boat haulers, and the 17 being a nightmare on Sundays afternoons as everyone returns home from being up north it can take a lot longer. Also in the winter it can be dicey if there is weather issues.
The Vegas route is a lot more predictable, easy drive as it is mostly on freeway. Usually you are not hitting Vegas traffic because typically one leaves PHX or Provo early in the morning.
Also depends where you are going in PHX north phoenix or EV then maybe page route. West phoenix then maybe Vegas route.
If you want to try to save 15-20 min with a possible frustrating drive in two way highways and being stuck behind truckers and RVs then thr Page route is your route. If you want an easier drive that’s predictable and almost entirely divided freeway then Vegas is your route.
I’ve been using the Vegas route more frequently recently because the page route was just kind of a frustrating drive more than not.