I too am waiting for miui 7 for my redmi 1s and note 4g .
Btw , I do not have any problems with miui 6 on both the phones .
^^
Yes , I find miui 6 ok . I'm not a gamer or a heavy user . Reading emails and news on the phone and watching YouTube and downloaded serials on my phones . I have not faced any problems so far .
BTW the battery life of my 1s and redmi note 4g is much better than my galaxy s4 , almost at par with my moto g 1st gen .