Taking into account verification, deposits / withdrawals, security, volume, fees, and service,
Which exchange can I register an account to complete verification the most convenient, transfer btc to fiat or transfer fiat to btc the maximum efficiency, then withdralal the fastest.
[...]
Where are you located? If you are in the same area as the bank that an exchange uses, it will speed things up significantly.
Regarding liquidity, sorted by monthly volume (notice: China exchanges have 0.- fees, so that's mostly bot trading):
http://bitcoincharts.com/markets/Coinbase
Lol, really? I heard of people waiting for a week for their coins. Doesn't sound that liquid to me.