I agree with OuncE, but so you have some opinion on the matter... i came from the Z and the Z1s, after that. If the z1s had an unlockable boot loader and was slightly cheaper, i probably would have kept it, but Ultimately the price, customizability and mostly comparable specs pulled me to the nexus.
USB otg has been a decent help with expanding the storage capacity, and custom kernels have great battery saving options. Beyond that, the Dev community and timely official updates make this phone pretty worth while, but that's just my opinion.
A parting piece of advice: you'll enjoy this phone more if you focus on what it can offer than if you focus on what it lacks.
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