Firstly, yahan ki warranty ky bare mai to mera koi acha view nahi hai, warranty mai koi bhi ho, company waly kehty hain ky ye ap ne jaan buj ky kiya hai, and all that bullshit stuff, to mere bhai yahan ki wareanty ka allah hi hafiz hai ...
Secondly, firmware ki setting ap khud karty ho, like ap auto updates khud select karty ho, atleast in my case, mujhay to ye option mili thi jab mai setting page open kiya tha in browser ...
Thirdly, jab koi bhi device unlock hoti hai, wo duniya mai har jaga use ki ja sakti hai, us mai chahy prepaid sim use karo for internet ya koi data sim ...
Forthly, ap pre-unlocked yani huawei, tp-link, ya koi bhi esi brand ko opt karty ho, to kafi expensive hoti hai, i searched for tp-link 4G M7350 device, it was available for 12K, yes 12K, so thats why i went for zong,s device and then unlocked it, afterthat, i also insert my father's prepaid sim in it, and yes it it got signals ....
So, in last, i would suggest you to get it unlocked, otherwise its your call