Probably considering the m7 has miui based on sence , but only 4.2.2 not 4.4._ that means IF it will ever happen it might be based on CM to be miui V5 , or based on sence 4.4 but it would be miui V6 .
But yet again it depends on miui devs and considering that only a few miui devices have V6 (4.4) i think it going to take some time for us to get some miui love .
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