http://gqwak27ypbucqjz62h7zlcebftu6wkzuc7lijgo6xqng5tfu33jz2lid.onion/bitcoin_guide
The main disadvantage is that you must pass KYC verification which involves scanning your ID and taking a selfie. It's a protection against money laundering. When you withdraw funds from exchange, you enter destination BTC address which is just an address.
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