Great phone with great specs but the software is not well optimised by Cyanogen or Yu to make it perform good.After updating to 5.1 from kitkat 4.4.4 phone is performing good as it was before in kitkat but battery drains too fast also heating has been increased a lot.they have released an incremental update on yuforums but issue is still there.
Issues in 5.1.1
Flash issue
Heating
App force closes & goes back to lock screen
Battery( SOT - 2.5-3 Hrs)