sissonne

YB- 665 will only reach by next week. I'll notify you once stock reach.

1. If payment made by this week can receive by next week? 
#sure,  we only need 1-2 working days for the goods to reach your place. Unless the model is unavailable.

2. For 3 pin adapter, can I use my original 3 pin adapter instead? Or must only use Yoobao's?
#you can use back your 3 pin adapter.

3. 2 outputs, if I use 2A output to charge my phone, it'll likely to charge faster right? But will there be any complications to the phone battery later?
#Yes will result in fast charge and fast drain as well.

4. This model still use Lithium Ion batteries right? How does it compare with Lithium Polymer's power bank such as Zerne, etc? Apparently Zerne sellers say that Yoobao's one is old-tech, cannot last as long, etc. 
#lithium polymer is not a new technology,  it has been in the market for decades. There is a reason for why big companies like Apple, Samsung still using Li ion. Only Sony uses lithium po.
The few reason is it's very costy and it's very dangerous due to its high discharge rate and can causes explosion if not handle properly

I bet you must have read about differences between Li ion and Li po through some seller who selling zerne PowerBank. Those articles can be very bias and misleading. Try Google yourself and see the pros and cons on this two.

Please let me know if you still have any questions.