Had problems with it once - was getting ~1/2 coins which i should be getting with my kh/s. Owner replied that GDC is forked/broken and it works like that.
Now, after almost 48 hours of mining DGB @ miningpool.co, i own 45k DGB.... Look at transactions: http://scr.hu/1a8/7uw4y (1k+ every ~hour = ~25k DGB / 24h)
With 4250 kh/s average, i should be getting around 48k DGB/24h, so i switched to smalltimeminer.com, and.... boom: 1 hour = 2,2k DGB - http://scr.hu/1a8/u1kyp
means ~53k/day !!
So be carefull while using miningpool.co guys
remember that atm difficulty is much lower than in the last 24h