Most pool take at least 1% fee, so added to ewbf 2%, nicehash is more or less equal in that regards 
some also could argue that if your aim is to mine an altcoin to transform it in BTC, they give you btc directly, so you also save on the transform fee. Anyway
I don't think you save anything with Nicehash, their exchange rate is lower than the current rates at poloniex/bittrex. At least that's what other users reported in EWBF thread and that's what WhatToMine says. In my opinion EQM miner should be at least 10-15% faster than EWBF to justify using it. Right now it's ~ 5-7% faster for me, so I switched to EWBF. Let's see whether Nicehash releases an update. some also could argue that if your aim is to mine an altcoin to transform it in BTC, they give you btc directly, so you also save on the transform fee. Anyway 
