Mi3 is the most worthy phone to buy at the moment.

Talking about LTE, what is the purpose to have an LTE mobile internet? Do we really need LTE speed for normal mobile internet (browsing, social etc)? I am living at Klang Valley so i can say that i am satisfied with my 3G. I do think LTE will be more worthy on downloading movies torrent and video streaming. But this will drain your data quota like hell. So end of the day, LTE is not that benefecial. I have a friend using s4 LTE, and he never  used LtE with the phone. He only set his network to 3G.

first time i hear LTE uses less battery compared to 3G 

ahhhh true but that applies only if you are a hard core mobile user.

1.2k but specs +/- about the same as mi3? except for:
- gorilla glass
- slightly wee bit smaller screen
- internal memory (or is 1.2k for same 16gb?)
- cameras lower

so.... why nexus5 then? 

3g is a-ok for me. i'm not data/speed hungry when i'm on the move
rom-wise, erm, typical female phone user. asalkan boleh fb, whatsapp, take pix, i'm a happy camper 

I wish they use back Qualcomm processor with wide range of LTE.

Qualcomm usually easier to build ROM by 3rd party dev.