I bought oneplus one on 1st january, 2015 after a long time wait to get invite, and got the device on 5th jan. The device first impressions were just killer, especially the device’s packaging and also the device look was very cool and the sandstone back of the phone feels awesome in hands. Now to the hardware the device hardware was also so cool, The device bears a snapdragon 801 processor with a 3Gb of ram which was great to handle all of your tasks and which can play high end games easily. The device comes with 16 or 64 gb memory option I bought the 64 gb variant which was more than enough and this device was really a flagship killer of that year.
The pros of phone are:-The processor which is a beast and plus the ram which makes it very fluid.
Secondly the great battery life which device gives.
Third is the cm11s kitkat(upgraded to cm12s lollipop now) was very fluid.
Cons of the phone were:-
1) some people get yellow tint is screen which was later fixed
2) the device heating problem that I used to face but it is fixed now
Other wise the phone is awesome for every task and also has killer looks I recommend this phone to all.!