I have used redmi 1s for about 1year . I have used 10 phones of different brand but the best phone is redmi 1s I had upgrade my redmi 1s to miui6 and kitkat and its work perfectly . there are some issues like heating problem, battery problem but in this range price this is best phone .
Upgrade to MIUI 7 its only ready china version right now, it doesn’t include google apps i.e playstore, google maps, google contact, etc. but dont worry, you can install them after. Like charging taking a whole lot of time. Well, surprisingly front cam quality enhanced in this rom as it now takes 1 MB pics approx. Whereas rear cam quality detoriated as its now taking only 1.5 MB pics.