This is MIUI V5 and 4.6.6 is the MIUI version which changes every week. first number is the Year, second number is the month, 3rd number is day of release which is always a Friday. Gapps working just fine?
yes its working i will use them for a long time and se it deep...and i will let you know if there will be any problem..
and now i think now we can say that this is a stable version.