Forex EA reviews provide you with a good starting point when you come to evaluating the performance of an automated Forex strategy. They can tell you about the system, its aims and objectives and also the likely performance that you will see from running the system on your account. However they can only provide you with so much information. The rest of the evaluation of a system is going to be down to you.
In order to successfully evaluate a system you will need to do some testing. Start by backtesting the system in order to see how it has performed in past market conditions. While this is not a true reflection of how it will perform in the future, it will nevertheless, give you an idea of how the strategy used generates profits and what to look out for. You can run backtests on any EA by using the built in strategy tester software in the MetaTrader 4 platform.