I use pbmining.com have over 500ghs on them and the payouts have been every week on time.
At the moment ghs is 0.0078btc in there.
If anyone is interested I would be very happy if someone would use my referral link http://pbmining.com?ref=Cryptonian.

EDIT: Also I use the Cex.io having over 400ghs in there aswell.. the maintance fees are quite a lot though but atleast you can sell the ghs back if you feel like it.

Would put it in signature but for some reason it removes it..
I guess because I am new.