The advantage is that you can also mining Litecoins and can be purchased KH, whose demand has increased in a few days. 
For BTC, the GHS / BTC ratio is less than CEX.io the price is quite cheap. The current price of BTC in Cex.io is 0.02371989 in BitMining is:
http://imageshack.com/a/img839/2214/yp4f.jpg
Finally, the commission is not as high as in CEX.io.
https://bit-mining.co/?ref=9705
You also get 5% of what your referrals earn daily

Scryptcc
Only allows mining BTC, in this you buy KHS with BTC. It also offers daily 5% of your referrals earnings.
http://scrypt.cc?ref=baa2D
http://imageshack.com/a/img89/8739/oazw.jpg