Yu Yureka is manufactured under the sub brand if micromax yu. I bought it and has been using for 6-7 months. The battery is very poor . The phone heats very quickly and its performance throttles down to avoid explosion. You cannot even touch it after playing asphalt 8 for 15 mins.
The cyanogenmod os is full of bugs. It comes with cm 11 built in which is somehow good but after that cm 12 and cm12.1 are bad. Cm 12.1 is the worst and it reboots automatically when you try to do multitasking and make phone calls.Inbuilt dialer is bad and I am using true dialer.It lags many times even after 2 gb ram and octa core processor. Definitely the is is not optimized for phone.