I haven't bought anything from them before, but this is far from their first phone. They've been designing and manufacturing phones for a while now, and from what I can tell, they're a reputable company. Having said that, they do push deadlines a bit, but they do release there products not long after. You can make your own judgement from their website, by searching "Elephone".
As for the phone, I'd expect everything to be true about it, however given their current record, they may delay shipping dates - it depends. This is their first 3GB RAM phone, but otherwise, they have experience in all other fields, including long battery life (you might want to check out the Elephone P5000), 1080p screens, camera sensors, perhaps not Android L (but would could go wrong), fingerprint sensors, 4G, the lot. What I'm trying to say is that I expect the P7000 to come out as they have delivered well across the board in the past, and even though they becoming a bit ambitious, they've got the foundations for their success all covered.
-Aspirin
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