Personally, I knew quite a number of samsung users changing to Sony Z1 and they are now aware of Z2. Previously they keep on buying samsung phones only.
Yup. I was all set to upgrade from my S3 to the S5 ... until I saw the look of the S5 (sigh ... not the same design again) and its specs (hardly better than the Note 3, worse in some areas).
So I started looking at alternatives and discovered the upcoming Sony Xperia Z2! I always saw Sony as a second tier Android manufacturer but the specs of the Z2 blew me away! The Z2 misses the fingerprint sensor, heart rate monitor, removable battery and phase detection autofocus of the S5, but in return, you get 1GB more RAM, bigger battery, metal/glass construction, very fluid UI and double-tap device on and off etc. And I was surprised to find that the Z2 will come with their equivalent of smart-stay, and various other motion features that I thought only existed on the Samsung.
I'm still deciding between the two but I think I'll go with the Z2. For those who have issues with the S5 for whatever reasons, I think you owe it to yourself to explore alternatives so that you can make a buying decision without regrets !