Both the 5.2" and 5.5" should last you the whole day with light usage. Used the 5.2" previously for a week, and the battery life is good.
The phone is underrated because people prefer specs rather than overall performance. To me as a user, it is actually doing pretty well. I do feel the upgrade coming from Xperia Z3 Compact, with better screen, better camera, better overall performance and better everyday battery life. The CPU performance isn't that bad compared to Snapdragon 650 and 652 but the GPU performance is noticeably lower, but I still manage to play all the games I'm playing on my phone smoothly.

Yeah, Asus isn't really well known for their phones, the first model Zenfones actually sold pretty well over here, but it does make a bad impression of having really low battery performance. Then came the 2nd generation with better battery performance but lacks built quality and great display. Now the third comes with great battery and great screen, even great camera but the launch price increase made people push it aside because base on their experience, it was not that good before with lower price, now with higher price, it simply becomes worse.

What do you guys think about the price of zenfone 3 zoom..rm 2099
Satu gadget going to have stock probably this evening

i find it strange that the asus zenfone 3 5.5" is snappier than xiaomi redmi note 3. Eventhough the RN3 have slightly better processor, the zenfone UI feels more responsive and faster. Maybe cause miui sucks but to those who say SD625 is slower then SD650, I would say not really.

personally, I think that asus zenfone is not worth it. Their phone overall quality is good but with the price they are selling, you can get other brand phones with better quality. For example, at RM2000, you can get one plus 3T, huawei mate 9 and so on that have better camera and SoC.

I got mine through phone plan so that is fine.

with 1.5k you can get

xiaomi mi 5 - better SoC with almost equally good camera.
oneplus 3  - better proc, 6gb memory and better camera
huawei p9 - better proc, better camera

comparing the 1.4k you can get with zenfone 5.5, i would rather add RM100 and get one plus 3. That SD625 is the deal breaker.

Seriously..this Asus Zenfone is not selling that well. A lot of review says the phone is overpriced which it is. It is definitely a good phone there is no denying that. The only people who think it is worth it either already bought it or did not do enough research. Please find me a review about Asus Zenfone that says it is a good buy with reasonable price. If you can find one, chances are it is paid review.

My reason of choosing the Zenfone 3 are :
1) Camera equipped with OIS for such low price
2) 64GB Storage and 4GB RAM below RM1100 (1st Quarter 2017) (Bought with discount + got ZenPower Pro)
3) Very good looking screen
4) Excellent design
5) Expandable storage
6) Good performance for the price
Nice, how is the game?