Poloniex still have lowest fee 0.0001 BTC. but if you can get profit i think fee will not be a problem. bittrex still have no problem record untill now even with high fee
Withdrawal fees should not be the only reason to decide for or against a particular exchange.
The actual trading fees are much more important, because you pay fees on every trade.
You can make hundreds of trades in a single day depending on your trading strategy while
you probably would withdraw funds only every few days.
Therefore I would rather look for an exchange with low trading fees than for an exchange with
cheap withdrawal fees. Actually, I´d even put more value on features like reliability and a good
trading engine than on a withdrawal fee that you only pay every once in a while.