Which is best?

[RiffoSai]

ASUS ZENFONE SELFIE ZD551KL, LENOVO VIBE SHOT Z90 BK and ASUS ZENFONE 2 ZE551. Those are the 3 phones I am looking at. I have doubts because I don't know:

1. Which is best for multitasking and gaming?

2. Is it true that quad-core 2.3gHz is better then quad 1.7+ quad 1 gHz?

3. Which phone has the best parts overall (the 2 asus ones got different types of processor models)+ is there bottlenecking in the phones (I've heard that some phones with 4gb ram still have some basic loading problems compared to some with 3gb which run smoothly)

I need help to decide which one is best and will be fine to use for the future 2-3years.

[xgn]

Best parts on a phone seriously? what about battery life camera and menu stuff most people care about

i can say i am happy about sony experia i had it for 3 years and there are newer better models of the same phone on the market now.

[RiffoSai]

Those 3 have the same battery life. I don't know much about phones and that's why I am wondering about the processor model, speed as well as the RAM. If you can explain me the 3 questions I have I would appreciate it.