No specialty ? I assume OP has one more specialty other than scam, probably he also own a Golden Hen which gives everyday 2-3 Golden eggs? Or maybe he has a magical money tree in his gardan that generates 50-70% return but he gives us only 15%-30%

Sad.
Yeah, I get the impression you haven't tried the site and are uninformed regarding how this business model works. However, if you were to spend an hour reading up on it, you would gain some insight into why it is possible to sell Bitcoin above spot price (hint: ebay, localbitcoins).
While everyone is entitled to an opinion, I usually wait until I have a little information before I comment. Up to that point, I generally ask questions - that way I can get to the point where I can form a coherent, informed opinion which I'm not embarrassed to share. But, again, that's just me....

To be honest, the only real downside to this platform is the support response time, which is truly dismal. Do not start trading on this site and expect your issues to be dealt with in a timely manner, because it's unlikely that they will be. However, there is a decent user community who are generally willing to assist and advise newbies.
Edit 1: BTW, it is only possible to consistently get a 15% premium (which is the minimum) as a seller - the competition of rates means that, in reality, anything above 15% is not realistically achievable.
Edit 2: Sorry about the smart-ass tone, I just dislike unhelpful, uninformed and troll-ish comments.... must try to be more patient in future

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