I tried Coinking for a few days, and I have some feedback.

FTC is listed as a scrypt coin, even though it switched to neoscrypt ages ago.

LTC profitability calculation seems erroneus giving about half of true value. As a result LTC is hardly mined at all, while other scrypt multipools mostly mine LTC.

SHA256 coins less profitable than Bitcoin seem to be mined too. Bitcoin hashing power should be forwarded to some larger no fee pool like other multipools do.

Automatic exhange seems not to work on some some coins.