Asus is using a slash and burn strategy. Everyone who buys in will get burned as they move on to the next model just mere months after they released the last one    I mean this is beyond stupid. All of us Zenfone 4 users would have gladly waited for the 4.5 if we had known about it. But no. They just had to announce it the month after we got our original Zenfones...which in itself was superseded by the 1600mAh version before the Zen 4.5 8MP version arrived. I mean for RM50 extra we could have gotten something we would have been truly satisfied with. Instead we were conned into preordering something that would arrive a month later than what we were promised and we had no way to get refunds in the meantime. Imagine our surprise and disgust when Asus announced the Zenfone 4.5 while we were holding the Zenfone 4 which was still warm from the factory (figuratively lah  )
Definitely over an hour. It takes at least an hour to charge my 1200mAh Zen 4 so it should take a lot longer than that to charge a Zen 5.