C2 is very good service for signal provider and one who wants to see audit results. They are very small and have share of problems but Mathew works to address all issues. Systems can be automated, semi-automated, or discretionary. There are high risks to any form of trading including system. But, with c2 you get to see what a trader/system did in real-time which is much more relevant then a historical backtest. It is best to look closely at what system developer writes and to look at the risk metrics of system before trading. There are many metrics to review and each trade can be reviewed. I change my goals and warn clearly that risk is likely higher in future. There are many bad systems on c2 but nobody says you have to trade them. You can use the grid to input metrics to find systems that have good criteria in terms of net return, risk/adjust return, # trades, etc. You can paper trade a system for free with OEC Cry. If you are serious about "making calls" then it provides the most accurate method that I know for tracking your results -- short of a real trade statements.
How does C2 work? They collect fee. It's no-loss-business (guess for whom?). Everybody can participate in this business by free donations.